Dose-response in direct comparisons of different doses of aspirin, ibuprofen and paracetamol (acetaminophen) in analgesic studies

Lessons learnt in evidence-based perioperative pain medicine: changing the focus from the medication and procedure to the patient

Over time, the focus of evidence-based acute pain medicine has shifted, from a focus on drugs and interventions (characterized by numbers needed to treat), to an appreciation of procedure-specific factors (characterized by guidelines and meta-analyses), and now anesthesiologists face the challenge to integrate our current approach with the concept of precision medicine. Psychometric and biopsychosocial markers can potentially guide clinicians on who may need more aggressive perioperative pain management, or who would respond particularly well to a given analgesic intervention. The challenge will be to identify an easily assessable set of parameters that will guide perioperative physicians in tailoring the analgesic strategy to procedure and patient.

The 125th Anniversary of Aspirin-The Story Continues

The year 2024 marks the 125th anniversary of aspirin, still one of the most frequently used drugs worldwide. Despite its veritable age, it is still relevant in pharmacotherapy and its use has spread to new areas over time. Due to aspirin's multiple pharmacological actions unified in one single molecule (i.e., analgesic, antipyretic, anti-inflammatory, antithrombotic, and antiviral effects), it continues to attract considerable attention in the scientific community and is subject to intense basic and clinical research. In fact, recent results confirmed aspirin's potential role as an antiviral drug and as an agent that can block harmful platelet functions in inflammatory/immunological processes. These features may open up new horizons for this ancient drug. The future of aspirin looks, therefore, bright and promising. Aspirin is not yet ready for retirement; on the contrary, its success story continues. This 125th anniversary paper will concisely review the various therapeutic uses of aspirin with a particular emphasis on the latest research results and their implications (e.g., use as an antiviral agent). In addition, the reader is provided with future perspectives for this remarkable drug.

An Updated Review on the Metabolite (AM404)-Mediated Central Mechanism of Action of Paracetamol (Acetaminophen): Experimental Evidence and Potential Clinical Impact

Paracetamol remains the recommended first-line option for mild-to-moderate acute pain in general population and particularly in vulnerable populations. Despite its wide use, debate exists regarding the analgesic mechanism of action (MoA) of paracetamol. A growing body of evidence challenged the notion that paracetamol exerts its analgesic effect through cyclooxygenase (COX)-dependent inhibitory effect. It is now more evident that paracetamol analgesia has multiple pathways and is mediated by the formation of the bioactive AM404 metabolite in the central nervous system (CNS). AM404 is a potent activator of TRPV₁, a major contributor to neuronal response to pain in the brain and dorsal horn. In the periaqueductal grey, the bioactive metabolite AM404 activated the TRPV₁ channel-mGlu5 receptor-PLC-DAGL-CB1 receptor signaling cascade. The present article provides a comprehensive literature review of the centrally located, COX-independent, analgesic MoA of paracetamol and relates how the current experimental evidence can be translated into clinical practice. The evidence discussed in this review established paracetamol as a central, COX-independent, antinociceptive medication that has a distinct MoA from non-steroidal anti-inflammatory drugs (NSAIDs) and a more tolerable safety profile. With the establishment of the central MoA of paracetamol, we believe that paracetamol remains the preferred first-line option for mild-to-moderate acute pain for healthy adults, children, and patients with health concerns. However, safety concerns remain with the high dose of paracetamol due to the NAPQI-mediated liver necrosis. Centrally acting paracetamol/p-aminophenol derivatives could potentiate the analgesic effect of paracetamol without increasing the risk of hepatoxicity. Moreover, the specific central MoA of paracetamol allows its combination with other analgesics, including NSAIDs, with a different MoA. Future experiments to better explain the central actions of paracetamol could pave the way for discovering new central analgesics with a better benefit-to-risk ratio.

Acetaminophen, Nonsteroidal Anti-Inflammatory Drugs, and Hypertension

Acetaminophen is widely regarded as a safe therapy for pain and fever in patients with cardiovascular disease and those taking anticoagulants. However, recent studies report that acetaminophen, like most other nonsteroidal anti-inflammatory drugs, increases blood pressure, and a formulation containing sodium increases cardiovascular risk. Those findings call into question guidelines recommending acetaminophen for patients with cardiovascular disease and pain, and those taking anticoagulants. We review evidence that acetaminophen has effects in common with nonsteroidal anti-inflammatory drugs, and its influence on coagulation via effects on vitamin K metabolism. Possible alternatives to acetaminophen for patients with pain are discussed.

Systematic reviews do not (yet) represent the 'gold standard' of evidence: A position paper

The low quality of included trials, insufficient rigour in review methodology, ignorance of key pain issues, small size, and over-optimistic judgements about the direction and magnitude of treatment effects all devalue systematic reviews, supposedly the 'gold standard' of evidence. Available evidence indicates that almost all systematic reviews in the published literature contain fatal flaws likely to make their conclusions incorrect and misleading. Only 3 in every 100 systematic reviews are deemed to have adequate methods and be clinically useful. Examples of research waste and questionable ethical standards abound: most trials have little hope of providing useful results, and systematic review of hopeless trials inspires no confidence. We argue that results of most systematic reviews should be dismissed. Forensically critical systematic reviews are essential tools to improve the quality of trials and should be encouraged and protected.

Analgesic effect of oral ibuprofen 400, 600, and 800 mg; paracetamol 500 and 1000 mg; and paracetamol 1000 mg plus 60 mg codeine in acute postoperative pain: a single-dose, randomized, placebo-controlled, and double-blind study

PURPOSE

Effect size estimates of analgesic drugs can be misleading. Ibuprofen (400 mg, 600 mg, 800 mg), paracetamol (1000 mg, 500 mg), paracetamol 1000 mg/codeine 60 mg, and placebo were investigated to establish the multidimensional pharmacodynamic profiles of each drug on acute pain with calculated effect size estimates.

METHODS

A randomized, double-blind, single-dose, placebo-controlled, parallel-group, single-centre, outpatient, and single-dose study used 350 patients (mean age 25 year, range 18 to 30 years) of homogenous ethnicity after third molar surgery. Primary outcome was sum pain intensity over 6 h. Secondary outcomes were time to analgesic onset, duration of analgesia, time to rescue drug intake, number of patients taking rescue drug, sum pain intensity difference, maximum pain intensity difference, time to maximum pain intensity difference, number needed to treat values, adverse effects, overall drug assessment as patient-reported outcome measure (PROM), and the effect size estimates NNT and NNTp.

RESULTS

Ibuprofen doses above 400 mg do not significantly increase analgesic effect. Paracetamol has a very flat analgesic dose-response profile. Paracetamol 1000/codeine 60 mg gives similar analgesia as ibuprofen from 400 mg, but has a shorter time to analgesic onset. Active drugs show no significant difference in maximal analgesic effect. Other secondary outcomes support these findings. The frequencies of adverse effects were low, mild to moderate in all active groups. NNT and NTTp values did not coincide well with PROMs.

CONCLUSION

Ibuprofen doses above 400 mg for acute pain offer limited analgesic gain. Paracetamol 1000 mg/codeine 60 mg is comparable to ibuprofen doses from 400 mg. Calculated effect size estimates and PROM in our study seem not to relate well as clinical analgesic efficacy estimators.

TRIAL REGISTRATION

NCT00699114.

Comparison of the Effectiveness of Pharmacological Treatments for Patients with Chronic Low Back Pain: A Nationwide, Multicenter Study in Japan

Introduction

Chronic low back pain (CLBP) is a leading cause of disability, yet there is limited high-quality evidence to identify the most suitable pharmacological therapy. The purpose of this Japanese nationwide, multicenter, prospective study was to compare the effectiveness of four representative drug therapies-acetaminophen, celecoxib, loxoprofen, and a tramadol and acetaminophen (T+A) combination drug-to establish evidence for a drug of choice for CLBP.

Methods

Patients with CLBP (N=471) received one of the four treatments and were evaluated, prospectively and comprehensively, once every month for six months using a visual analog scale (VAS) for LBP, the Japanese Orthopedic Association (JOA) score, the JOA Back Pain Evaluation Questionnaire (JOABPEQ), the Roland-Morris Disability Questionnaire (RDQ), the EuroQol five-dimensions three-levels (EQ-5D-3L), and the Short Form-8 item health survey (SF-8). We conducted multivariable linear regression analyses of the four drugs at 1 and 6 months after drug allocation. Differences with P<0.05 were considered statistically significant.

Results

Patients who received acetaminophen showed a significant improvement from baseline in the mental health subscale of the JOABPEQ at one month (P=0.02) and the JOA score at six months (P<0.01). None of the other outcome measures among the four drugs differed significantly. Across groups, all outcome measures, except the mental component summary (MCS) score of the SF-8, improved equivalently, although most measurements showed no obvious cumulative effect over six months. The MCS score of the SF-8 decreased gradually over six months in all groups.

Conclusions

Most of the outcome measures among the treated groups were not significantly different, indicating similar treatment effects of the four drugs for CLBP. Our study indicated the limit of each outcome measure for evaluating the patient status, suggesting that a single outcome measure is insufficient to reflect treatment effectiveness.

Lewis acid-promoted site-selective cyanation of phenols

An efficient Lewis acid-promoted site-selective electrophilic cyanation of 3-substituted and 3,4-disubstituted phenols has been developed. The cyanation reactions using MeSCN as the cyanating reagent proceeded efficiently to afford a wide range of 2-hydroxybenzonitriles with high efficiency and excellent regioselectivity. This protocol could provide a practical method for the synthesis and modification of biologically active molecules.

Optimizing Pain Control and Minimizing Opioid Use in Trauma Patients

Adverse effects of opioids and the ongoing crisis of opioid abuse have prompted providers to reduce prescribing opioids and increase use of multiple nonpharmacologic therapies, nonopioid analgesics, and co-analgesics for pain management in trauma patients. Nonopioid agents, including acetaminophen, nonsteroidal anti-inflammatory drugs, gabapentinoids, ketamine, central α2 agonists, and lidocaine, can be used as adjuncts or alternatives to opioids in the trauma population. Complementary therapies such as acupuncture, virtual reality, and mirror therapy are modalities that also may be helpful in reducing pain. Performing pain assessments is fundamental to identify pain and evaluate treatment effectiveness in the critically ill trauma patient. The efficacy, safety, and availability of opioid-sparing therapies and multimodal pain regimens are reviewed.

Paracetamol/acetaminophen (single administration) for perineal pain in the early postpartum period

BACKGROUND

Perineal pain is a common but poorly studied adverse outcome following childbirth. Pain may result from perineal trauma due to bruising, spontaneous tears, surgical incisions (episiotomies), or in association with operative vaginal births (ventouse or forceps-assisted births). This is an update of a review last published in 2013.

OBJECTIVES

To determine the efficacy of a single administration of paracetamol (acetaminophen) used in the relief of acute postpartum perineal pain.

SEARCH METHODS

For this update, we searched the Cochrane Pregnancy and Childbirth's Trials Register, ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (9 December 2019), and reference lists of retrieved studies.

SELECTION CRITERIA

Randomised controlled trials (RCTs), including cluster-RCTs, comparing paracetamol to placebo. We excluded quasi-RCTs and cross-over trials. Data from abstracts would be included only if authors had confirmed in writing that the data to be included in the review had come from the final analysis and would not change.

DATA COLLECTION AND ANALYSIS

Two review authors assessed each study for inclusion and extracted data. One review author reviewed the decisions and confirmed calculations for pain relief scores. We assessed the certainty of the evidence using the GRADE approach.

MAIN RESULTS

This update identified no new trials so the results remain unchanged. However, by applying the GRADE assessment of the evidence, the interpretation of main results differed from previous version of this review. We identified 10 studies involving 2044 women, but all these studies involved either three or four groups, looking at differing drugs or doses. We have only included the 1301 women who were in the paracetamol versus placebo arms of the studies. Of these, five studies (482 women) assessed 500 mg to 650 mg and six studies (797 women) assessed 1000 mg of paracetamol. One study assessed 650 mg and 1000 mg compared with placebo and contributed to both comparisons. We used a random-effects meta-analysis because of the clinical variability among studies. Studies were from the 1970s to the early 1990s, and there was insufficient information to assess the risk of bias adequately, hence the findings need to be interpreted within this context. The certainty of the evidence for the two primary outcomes on which data were available was assessed as low, downgraded for overall unclear risk of bias and for heterogeneity (I² statistic 60% or greater). More women may experience pain relief with paracetamol compared with placebo (average risk ratio (RR) 2.14, 95% confidence interval (CI) 1.59 to 2.89; 10 trials, 1279 women), and fewer women may need additional pain relief with paracetamol compared with placebo (average RR 0.34, 95% CI 0.21 to 0.55; 8 trials, 1132 women). However, the certainty of the evidence was low, downgraded for unclear overall risk of bias and substantial heterogeneity. One study used the higher dose of paracetamol (1000 mg) and reported maternal drug adverse effects. There may be little or no difference in the incidence of nausea (average RR 0.18, 95% CI 0.01 to 3.66; 1 trial, 232 women; low-certainty evidence), or sleepiness (average RR 0.89, 95% CI 0.18 to 4.30; 1 trial, 232 women; low-certainty evidence). No other maternal adverse events were reported. None of the studies assessed neonatal drug adverse effects.

AUTHORS' CONCLUSIONS

A single dose of paracetamol may improve perineal pain relief following vaginal birth, and may reduce the need for additional pain relief. Potential adverse effects for both women and neonates were not appropriately assessed. Any further trials should also address the gaps in evidence concerning maternal outcomes such as satisfaction with postnatal care, maternal functioning/well-being (emotional attachment, self-efficacy, competence, autonomy, confidence, self-care, coping skills) and neonatal drug adverse effects.

Comparison between isolated and associated with codeine acetaminophen in pain control of acute apical abscess: a randomized clinical trial

OBJECTIVES

The study aimed to compare the acetaminophen administration efficacy or its combination with codeine for pain control in acute apical abscesses cases.

MATERIALS AND METHODS

Thirty-nine patients who sought emergency treatment in the Faculty of Dentistry of the Federal University of Rio Grande do Sul were included, all of them with acute apical abscess diagnosis. These patients were divided into two groups: acetaminophen group-prescription of acetaminophen (1000 mg) and acetaminophen-codeine group-prescription of acetaminophen (1000 mg) + codeine (30 mg), both with oral intake every 6 h for 3 days. The pain scores were recorded by the patients on their own at 6, 12, 24, 48, and 72 h after finishing clinical assistance, by filling a pain evolution journal, containing a visual analogue scale (VAS). Student t test was conducted to investigate different mean ages between groups 1 and 2. A comparison of weight and means of initial pain scores between groups was carried out using the Mann-Whitney U test. Chi-square test was performed to compare gender, affected tooth, education, initial swelling, and frequency of adverse effect between test and control groups. Mann-Whitney U test was applied to compare groups in the same period. Friedman's test was used to compare results from the same group over time.

RESULTS

Both groups showed score reduction over time (P < 0.05). Paracetamol-codeine group showed significant pain score reduction at 48 h registers when compared to baseline and at 6 h scores (P < 0.05). Further, pain scores at 72 h were significantly lower, when compared to the baseline, at 6 h, and at 12 h scores (P < 0.05). Acetaminophen group showed significant pain score reduction observed at 72 h, when compared to the baseline and at 6 h scores (P < 0.05). There were no significant differences in pain score reduction over time between groups (P > 0.05). There was no difference between the groups regarding the frequency of adverse reactions (P > 0.05).

CONCLUSION

Both medications were effective for pain control in acute apical abscess cases. The findings might have inferred in pain control of acute apical abscess associated pain in patients who used an antibiotic drug. External validity of the findings for acute apical abscess cases with no need for an antibiotic prescription is uncertain.

CLINICAL RELEVANCE

This paper suggests acetaminophen 1000 mg can be used for pain control in the treatment of acute apical abscess associated with systemic manifestation.

Comparing the prophylactic effects of oral gabapentin, pregabalin, and celecoxib on postoperative pain management in orthopedic surgery of the lower extremity: A double-blind randomized controlled trial

Background:

Lower extremity pain after orthopedic surgery is so frequent that has led to many treatment modalities. This study aims to compare the prophylactic effects of oral gabapentin, pregabalin, and celecoxib on reducing postsurgical pain of the lower extremity orthopedic surgery.

Materials and Methods:

In a double-blind randomized controlled trial, 120 patients were randomly divided into four groups using block design randomization. 1 h before spinal anesthesia, the studied groups received 300 mg oral gabapentin; 75 mg oral pregabalin; 200 mg oral celecoxib; and starch as placebo. The severity of postoperative pain (using visual analog scale), mean arterial pressure, heart rate, opioid consumption dose, and drug side effects were recorded for six times (each 60 min up to two times and then every 6 h for the next four times). Chi-square, one-way analysis of variance (ANOVA), and ANOVA repeated measure tests were used for statistical analysis.

Results:

Significant reduction of pain severity was observed only at the first time measurement between pregabalin and placebo groups (P: 0.014). Patients in the pregabalin group required lower dose of opioid compared to placebo group during admission in surgical ward. There were no significant differences concerning pain reduction, opioid administration, and side effects between pregabalin, gabapentin, and celecoxib groups.

Conclusion:

Taking 75 mg oral pregabalin before lower extremity orthopedic surgery can attenuate postoperative pain, especially during the 1^st h postoperation as well as less opioid consumption and much more patients' satisfaction.

Application of the relationship between pharmacokinetics and pharmacodynamics in drug development and therapeutic equivalence: a PEARRL review

Objectives

The objective of this review was to provide an overview of pharmacokinetic/pharmacodynamic (PK/PD) models, focusing on drug-specific PK/PD models and highlighting their value added in drug development and regulatory decision-making.

Key findings

Many PK/PD models, with varying degrees of complexity and physiological understanding have been developed to evaluate the safety and efficacy of drug products. In special populations (e.g. paediatrics), in cases where there is genetic polymorphism and in other instances where therapeutic outcomes are not well described solely by PK metrics, the implementation of PK/PD models is crucial to assure the desired clinical outcome. Since dissociation between the pharmacokinetic and pharmacodynamic profiles is often observed, it is proposed that physiologically based pharmacokinetic and PK/PD models be given more weight by regulatory authorities when assessing the therapeutic equivalence of drug products.

Summary

Modelling and simulation approaches already play an important role in drug development. While slowly moving away from ‘one-size fits all’ PK methodologies to assess therapeutic outcomes, further work is required to increase confidence in PK/PD models in translatability and prediction of various clinical scenarios to encourage more widespread implementation in regulatory decision-making.

Estimating relative efficacy in acute postoperative pain: network meta-analysis is consistent with indirect comparison to placebo alone

Network meta-analysis uses direct comparisons of interventions within randomized controlled trials and indirect comparisons across them. Network meta-analysis uses more data than a series of direct comparisons with placebo, and theoretically should produce more reliable results. We used a Cochrane overview review of acute postoperative pain trials and other systematic reviews to provide data to test this hypothesis. Some 261 trials published between 1966 and 2016 included 39,753 patients examining 52 active drug and dose combinations (27,726 given active drug and 12,027 placebo), in any type of surgery (72% dental). Most trials were small; 42% of patients were in trials with arms <50 patients, and 27% in trials with arms ≥100 patients. Response to placebo in third molar extraction fell by half in studies over 30 to 40 years (171 trials, 7882 patients given placebo). Network meta-analysis and Cochrane analyses provided very similar results (average difference 0.04 number needed to treat units), with no significant difference for almost all comparisons apart from some with small patient numbers or small effect size, or both. Network meta-analysis did not detect significant differences between effective analgesics. The similarity between network meta-analysis and Cochrane indirect analyses probably arose from stringent quality criteria in trials accepted in Cochrane reviews (with consequent low risk of bias) and consistency in methods and outcomes. Network meta-analysis is a useful analytical tool that increases our confidence in estimates of efficacy of analgesics in acute postoperative pain, in this case by providing similar results.

Analgesic effectiveness, pharmacokinetics, and safety of a paracetamol/ibuprofen fixed-dose combination in children undergoing adenotonsillectomy: A randomized, single-blind, parallel group trial

BACKGROUND

Pain following tonsillectomy is often poorly managed in the home setting. Multimodal analgesia with acetaminophen (paracetamol) and nonsteroidal anti-inflammatory drugs offers superior analgesia over monotherapy but may be difficult for caregivers to manage. A fixed-dose combination oral suspension product containing paracetamol and ibuprofen has been developed to facilitate pediatric dosing.

AIMS

The aims of this study are to determine the analgesic effectiveness, pharmacokinetics, and safety of the fixed-dose combination at two doses in the pediatric population.

METHODS

In this prospective, multicenter, randomized, single-blind, parallel group trial, 251 children aged 2-12 years undergoing day-stay (adeno)tonsillectomy were randomized to two dose groups of the fixed-dose combination. A doubled loading dose was given preoperatively, followed by treatment for up to 11 days (Higher dose: paracetamol 15 mg/kg + ibuprofen 4.5 mg/kg, Lower dose: paracetamol 12 mg/kg + ibuprofen 3.6 mg/kg). Blood samples were collected for pharmacokinetic analysis for up to 6 hours after the loading dose. The analgesic effectiveness was examined on the first day after surgery using both Parents Postoperative Pain Measurement and modified Wong-Baker Faces pain scales. Rescue medication consumption was recorded throughout the study.

RESULTS

Differences in maximum plasma concentration (C_max ) and total exposure (AUC_0→t ) between the treatment groups for both analytes were consistent with a 25% increase in dose; there was no difference in time to peak concentration (T_max ). On the first postoperative day, there was no difference in pain scores or rescue medication use between treatment groups (approximately 30% in both groups). The combination was well tolerated by both groups. The most common adverse events were vomiting and nausea. The incidence of postoperative bleeding was 4.4%.

CONCLUSION

The shallow dose-response relationship and good tolerability of the fixed-dose combination over an extended study period supports the utility of both doses of the fixed-dose combination in the home setting.

Effects of high- and low-dose aspirin on adaptive immunity and hypertension in the stroke-prone spontaneously hypertensive rat

Despite its well-known antithrombotic properties, the effect of aspirin on blood pressure (BP) and hypertension pathology is unclear. The hugely varying doses used clinically have contributed to this confusion, with high-dose aspirin still commonly used due to concerns about the efficacy of low-dose aspirin. Because prostaglandins have been shown to both promote and inhibit T-cell activation, we also explored the immunomodulatory properties of aspirin in hypertension. Although the common preclinical high dose of 100 mg/kg/d improved vascular dysfunction and cardiac hypertrophy, this effect was accompanied by indices of elevated adaptive immunity, renal T-cell infiltration, renal fibrosis, and BP elevation in stroke-prone spontaneously hypertensive rats and in angiotensin II-induced hypertensive mice. The cardioprotective effects of aspirin were conserved with a lower dose (10 mg/kg/d) while circumventing heightened adaptive immunity and elevated BP. We also show that low-dose aspirin improves renal fibrosis. Differential inhibition of the COX-2 isoform may underlie the disparate effects of the 2 doses. Our results demonstrate the efficacy of low-dose aspirin in treating a vast array of cardiovascular parameters and suggest modulation of adaptive immunity as a novel mechanism underlying adverse cardiovascular profiles associated with COX-2 inhibitors. Clinical studies should identify the dose of aspirin that achieves maximal cardioprotection with a new awareness that higher doses of aspirin could trigger undesired autoimmunity in hypertensive individuals. This work also warrants an evaluation of high-dose aspirin and COX-2 inhibitor therapy in sufferers of inflammatory conditions who are already at increased risk for cardiovascular disease.-Khan, S. I., Shihata, W. A., Andrews, K. L., Lee, M. K. S., Moore, X.-L., Jefferis, A.-M., Vinh, A., Gaspari, T., Dragoljevic, D., Jennings, G. L., Murphy, A. J., Chin-Dusting, J. P. F. Effects of high- and low-dose aspirin on adaptive immunity and hypertension in the stroke-prone spontaneously hypertensive rat.

Effect of Nonsteroidal Anti-inflammatory Drug as an Oral Premedication on the Anesthetic Success of Inferior Alveolar Nerve Block in Treatment of Irreversible Pulpitis: A Systematic Review with Meta-analysis and Trial Sequential Analysis

INTRODUCTION

Successful anesthesia with an inferior alveolar nerve block (IANB) is imperative for treating patients with irreversible pulpitis in mandibular teeth. This systematic review assessed the efficacy of nonsteroidal anti-inflammatory drugs (NSAIDs) as oral premedications on the success of IANBs in irreversible pulpitis.

METHODS

Three databases were searched to identify randomized clinical trials (RCTs) published up until September 2017. Retrieved RCTs were evaluated using the revised Cochrane Risk of Bias Tool. The primary efficacy outcome of interest was the success rate of IANB anesthesia. Meta-analytic estimates (risk ratio [RR] with 95% confidence intervals [CIs]) performed using a random effects model and publication bias determined using funnel plot analysis were assessed. Random errors were evaluated with trial sequential analyses, and the quality of evidence was appraised using a Grading of Recommendations, Assessment, Development and Evaluation approach.

RESULTS

Thirteen RCTs (N = 1034) were included. Eight studies had low risk of bias. Statistical analysis of good-quality RCTs showed a significant beneficial effect of any NSAID in increasing the anesthetic success of IANBs compared with placebo (RR = 1.92; 95% CI, 1.55-2.38). Subgroup analyses showed a similar beneficial effect for ibuprofen, diclofenac, and ketorolac (RR = 1.83 [95% CI, 1.43-2.35], RR = 2.56 [95% CI, 1.46-4.50], and RR = 2.07 [95% CI, 1.47-2.90], respectively). Dose-dependent ibuprofen >400 mg/d (RR = 1.85; 95% CI, 1.39-2.45) was shown to be effective; however, ibuprofen ≤400 mg/d showed no association (RR = 1.78; 95% CI, 0.90-3.55). TSA confirmed conclusive evidence for a beneficial effect of NSAIDs for IANB premedication. The Grading of Recommendations, Assessment, Development and Evaluation approach did not reveal any concerns regarding the quality of the results.

CONCLUSIONS

Oral premedication with NSAIDs and ibuprofen (>400 mg/d) increased the anesthetic success of IANBs in patients with irreversible pulpitis.

Effectiveness of median nerve neural mobilization versus oral ibuprofen treatment in subjects who suffer from cervicobrachial pain: a randomized clinical trial

INTRODUCTION

Oral ibuprofen (OI) and median nerve neural mobilization (MNNM) are first line treatments for patients who suffer cervicobrachial pain (CP). OI may produce side effects which are not tolerated by all subjects who suffer CP, whereas MNNM has no known side effects. Therefore, the aim of this study was to assess the effectiveness of both treatments (OI vs. MNNM) in CP.

MATERIAL AND METHODS

This investigation was a blinded parallel randomized clinical trial (NCT02593721). Sixty-two participants diagnosed with CP were recruited and randomly assigned to 2 groups (n = 31), which received MNNM or 1200 mg/day OI treatment for 6 weeks. The numeric rating scale for pain intensity was the primary outcome. The cervical rotation range of motion (CROM) and the upper limb function were the secondary outcomes.

RESULTS

The results showed that OI treatment (η2 = 0.612-0.755) was clearly superior to MNNM (η2 = 0.816-0.821) in all assessments (p < 0.05) except for the CROM device results, which were equivalent to those of the MNNM group (p > 0.05). Three subjects were discharged because of OI side effects.

CONCLUSIONS

Oral ibuprofen may be superior to MNNM for pain reduction and upper limb function increase of subjects with CP. Nevertheless, both treatments were effective. Median nerve neural mobilization may be considered an effective non-pharmaceutical treatment option in subjects with CP. Regarding OI adverse effects, our findings challenge the role of pharmacologic versus manual therapy as possible treatments that may improve pain intensity and upper limb functionality in subjects with CP.

Trends in analgesic consumption in France over the last 10 years and comparison of patterns across Europe

AIMS

The aims of the present study were to describe the consumption trends of three groups of analgesics (non-opioids, and mild and strong opioids) between 2006 and 2015 in France, and compare this pattern of use with six European countries in 2015.

METHODS

Annual drugs sales were extracted from the French national authority's consumption database, and from the IMS Multinational Integrated Data Analysis System and national databases for European countries.

RESULTS

The use of mild opioids in France was found to have decreased by 53% over the past 10 years, owing to the declining use of dextropropoxyphene combinations, along with an increase in the use of non-opioids and strong opioids (from 72 to 93, and 2 to 2.8 defined daily doses/1000 inhabitants/day, respectively). Paracetamol, the most consumed analgesic, increased over this period, particularly for the adult high dose (+140%). The use of tramadol and codeine combinations also increased, by 62% and 42%, respectively. Morphine remained the most used strong opioid, although there were also large increases in the consumption of oxycodone (+613%) and fentanyl (+263% and +72% for transmucosal and transdermal forms, respectively). A comparison of the patterns of use in Europe in 2015 showed a higher consumption of mild and strong opioids in the UK. France ranked first and third place, respectively, for paracetamol and mild opioid consumption, whereas its use of strong opioids was among the lowest.

CONCLUSIONS

Paracetamol consumption is clearly highest in France, whereas its use of strong opioids is among the lowest in Europe, although its consumption of oxycodone has increased significantly. Further studies are required specifically to monitor these drugs.

Is pharmacologic treatment better than neural mobilization for cervicobrachial pain? A randomized clinical trial

Purpose: This study aim was to compare the effectiveness of the median nerve neural mobilization (MNNM) and cervical lateral glide (CLG) intervention versus oral ibuprofen (OI) in subjects who suffer cervicobrachial pain (CP). Methods: This investigation was a, multicenter, blinded, randomized controlled clinical trial (NCT02595294; NCT02593721). A number of 105 individuals diagnosed with CP were enrolled in the study and treated in 2 different medical facilities from July to November 2015. Participants were recruited and randomly assigned into 3 groups of 35 subjects. Intervention groups received MNNM or CLG neurodynamic treatments, and the (active treatment) control group received an OI treatment for 6 weeks. Primary outcome was pain intensity reported through the Numeric Rating Scale for Pain (NRSP). Secondary outcomes were physical function involving the affected upper limb using the Quick DASH scale, and ipsilateral cervical rotation (ICR) using a cervical range of motion (CROM) device. Assessments were performed before and 1 hour after treatment for NRSP (baseline, 3 and 6 weeks) and CROM (baseline and 6 weeks), as well as only 1 assessment for Quick DASH (baseline and 6 weeks). Results: Repeated-measures ANOVA intergroup statistically significant differences were shown for CP intensity (F(2,72) = 22.343; P < .001; Eta2 = 0.383) and Quick DASH (F(2,72) = 15.338; P < .001; Eta2 = 0.299), although not for CROM (F(2,72) = 1.434; P = .245; Eta2 = 0.038). Indeed, Bonferroni´s correction showed statistically significant differences for CP intensity (P < .01; 95% CI = 0.22 - 3.26) and Quick DASH reduction (P < .01; 95% CI = 8.48 - 24.67) in favor of the OI treatment at all measurement moments after baseline. Conclusions: OI pharmacologic treatment may reduce pain intensity and disability with respect to neural mobilization (MNNM and CLG) in patients with CP during six weeks. Nevertheless, the non-existence of between-groups ROM differences and possible OI adverse effects should be considered.

Antinociceptive and Antibacterial Properties of Anthocyanins and Flavonols from Fruits of Black and Non-Black Mulberries

Anthocyanins and flavones are important pigments responsible for the coloration of fruits. Mulberry fruit is rich in anthocyanins and flavonols, which have multiple uses in traditional Chinese medicine. The antinociceptive and antibacterial activities of total flavonoids (TF) from black mulberry (MnTF, TF of Morus nigra) and non-black mulberry (MmTF, TF of Morus mongolica; and MazTF, TF of Morus alba 'Zhenzhubai') fruits were studied. MnTF was rich in anthocyanins (11.3 mg/g) and flavonols (0.7 mg/g) identified by ultra-performance liquid chromatography-tunable ultraviolet/mass single-quadrupole detection (UPLC-TUV/QDa). Comparatively, MmTF and MazTF had low flavonol contents and MazTF had no anthocyanins. MnTF showed significantly higher antinociceptive and antibacterial activities toward Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus than MmTF and MazTF. MnTF inhibited the expression of interleukin 6 (IL-6), inducible nitric oxide synthase (iNOS), phospho-p65 (p-p65) and phospho-IκBα (p-IκBα), and increased interleukin 10 (IL-10). Additionally, mice tests showed that cyanidin-3-O-glucoside (C3G), rutin (Ru) and isoquercetin (IQ) were the main active ingredients in the antinociceptive process. Stronger antinociceptive effect of MnTF was correlated with its high content of anthocyanins and flavonols and its inhibitory effects on proinflammatory cytokines, iNOS and nuclear factor-κB (NF-κB) pathway-related proteins.

Pain relief of sore throat with a new anti-inflammatory throat lozenge, ibuprofen 25 mg: A randomised, double-blind, placebo-controlled, international phase III study

OBJECTIVE

The aim of this study was to compare the efficacy and safety of a new oromucosal ibuprofen form, ibuprofen 25 mg lozenge, in single and repeat dosing for up to 4 days, to the matched placebo, in the treatment of acute sore throat pain in adults.

METHODS

In this randomised, double-blind, placebo-controlled trial, adult patients with non-streptococcal sore throat and signs of moderate-to-severe associated pain (≥5 on the objective Tonsillo-Pharyngitis Assessment 21-point scale and ≥60 mm on the subjective 0-100 mm visual analogue Sore Throat Pain Intensity Scale [STPIS]) were assigned ibuprofen 25 mg (n=194) or matching placebo (n=191) lozenge treatment. Efficacy was assessed (at the investigating centre up to 2 hours after first dosing, then on an ambulatory basis) by parameters derived from patient's scores on scales of pain relief, pain intensity, and global efficacy assessment. The primary efficacy end-point was the time-weighted TOTal PAin Relief (TOTPAR) over 2 hours after first dosing using the Sore Throat Relief Scale (STRS). Safety and local tolerability were assessed.

RESULTS

Ibuprofen 25 mg was superior to placebo on numerous pain relief parameters; TOTPAR was significantly higher with ibuprofen 25 mg over 2 hours after first dosing (P<.05), the effect being apparent from the first evaluation at 15 minutes (P<.05). The STPIS reduction in favour of ibuprofen 25 mg was not significant vs placebo. Mean STRS scores and patient's global efficacy assessment both reflected a higher efficacy of ibuprofen 25 mg over the 4-day treatment period with tests of statistical significance up to day 1 evening (P<.05), and, in patients with still clinically significant pain (n=128), after an average 4 days (P<.01). Ibuprofen 25 mg lozenge was well tolerated with a safety profile similar to placebo.

CONCLUSION

Low-dose ibuprofen 25 mg lozenge in repeat dosing provides in adults more efficacious and rapid relief of sore throat pain and is as well tolerated as placebo.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, NCT01785862.

Drug repurposing in cancer

Cancer is a major health issue worldwide, and the global burden of cancer is expected to increase in the coming years. Whereas the limited success with current therapies has driven huge investments into drug development, the average number of FDA approvals per year has declined since the 1990s. This unmet need for more effective anti-cancer drugs has sparked a growing interest for drug repurposing, i.e. using drugs already approved for other indications to treat cancer. As such, data both from pre-clinical experiments, clinical trials and observational studies have demonstrated anti-tumor efficacy for compounds within a wide range of drug classes other than cancer. Whereas some of them induce cancer cell death or suppress various aspects of cancer cell behavior in established tumors, others may prevent cancer development. Here, we provide an overview of promising candidates for drug repurposing in cancer, as well as studies describing the biological mechanisms underlying their anti-neoplastic effects.

Oral nonsteroidal anti-inflammatory drugs (NSAIDs) for cancer pain in adults

BACKGROUND

Pain is a common symptom with cancer, and 30% to 50% of all people with cancer will experience moderate to severe pain that can have a major negative impact on their quality of life. Non-opioid drugs are commonly used to treat cancer pain, and are recommended for this purpose in the World Health Organization (WHO) cancer pain treatment ladder, either alone or in combination with opioids.A previous Cochrane review that examined the evidence for nonsteroidal anti-inflammatory drugs (NSAIDs) or paracetamol, alone or combined with opioids, for cancer pain was withdrawn in 2015 because it was out of date; the date of the last search was 2005. This review, and another on paracetamol, updates the evidence.

OBJECTIVES

To assess the efficacy of oral NSAIDs for cancer pain in adults, and the adverse events reported during their use in clinical trials.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, and Embase from inception to April 2017, together with reference lists of retrieved papers and reviews, and two online study registries.

SELECTION CRITERIA

We included randomised, double-blind, single-blind, or open-label studies of five days' duration or longer, comparing any oral NSAID alone with placebo or another NSAID, or a combination of NSAID plus opioid with the same dose of the opioid alone, for cancer pain of any pain intensity. The minimum study size was 25 participants per treatment arm at the initial randomisation.

DATA COLLECTION AND ANALYSIS

Two review authors independently searched for studies, extracted efficacy and adverse event data, and examined issues of study quality and potential bias. We did not carry out any pooled analyses. We assessed the quality of the evidence using GRADE and created a 'Summary of findings' table.

MAIN RESULTS

Eleven studies satisfied inclusion criteria, lasting one week or longer; 949 participants with mostly moderate or severe pain were randomised initially, but fewer completed treatment or had results of treatment. Eight studies were double-blind, two single-blind, and one open-label. None had a placebo only control; eight compared different NSAIDs, three an NSAID with opioid or opioid combination, and one both. None compared an NSAID plus opioid with the same dose of opioid alone. Most studies were at high risk of bias for blinding, incomplete outcome data, or small size; none was unequivocally at low risk of bias.It was not possible to compare NSAIDs as a group with another treatment, or one NSAID with another NSAID. Results for all NSAIDs are reported as a randomised cohort. We judged results for all outcomes as very low-quality evidence.None of the studies reported our primary outcomes of participants with pain reduction of at least 50%, and at least 30%, from baseline; participants with Patient Global Impression of Change (PGIC) of much improved or very much improved (or equivalent wording). With NSAID, initially moderate or severe pain was reduced to no worse than mild pain after one or two weeks in four studies (415 participants in total), with a range of estimates between 26% and 51% in individual studies.Adverse event and withdrawal reporting was inconsistent. Two serious adverse events were reported with NSAIDs, and 22 deaths, but these were not clearly related to any pain treatment. Common adverse events were thirst/dry mouth (15%), loss of appetite (14%), somnolence (11%), and dyspepsia (11%). Withdrawals were common, mostly because of lack of efficacy (24%) or adverse events (5%).

AUTHORS' CONCLUSIONS

There is no high-quality evidence to support or refute the use of NSAIDs alone or in combination with opioids for the three steps of the three-step WHO cancer pain ladder. There is very low-quality evidence that some people with moderate or severe cancer pain can obtain substantial levels of benefit within one or two weeks.

Oral paracetamol (acetaminophen) for cancer pain

BACKGROUND

Pain is a common symptom with cancer, and 30% to 50% of all people with cancer will experience moderate to severe pain that can have a major negative impact on their quality of life. Non-opioid drugs are commonly used to treat mild to moderate cancer pain, and are recommended for this purpose in the WHO cancer pain treatment ladder, either alone or in combination with opioids.A previous Cochrane review that examined the evidence for nonsteroidal anti-inflammatory drugs (NSAIDs) or paracetamol, alone or combined with opioids, for cancer pain was withdrawn in 2015 because it was out of date; the date of the last search was 2005. This review, and another on NSAIDs, updates the evidence.

OBJECTIVES

To assess the efficacy of oral paracetamol (acetaminophen) for cancer pain in adults and children, and the adverse events reported during its use in clinical trials.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, and Embase from inception to March 2017, together with reference lists of retrieved papers and reviews, and two online study registries.

SELECTION CRITERIA

We included randomised, double-blind, studies of five days' duration or longer, comparing paracetamol alone with placebo, or paracetamol in combination with an opioid compared with the same dose of the opioid alone, for cancer pain of any intensity. Single-blind and open studies were also eligible for inclusion. The minimum study size was 25 participants per treatment arm at the initial randomisation.

DATA COLLECTION AND ANALYSIS

Two review authors independently searched for studies, extracted efficacy and adverse event data, and examined issues of study quality and potential bias. We did not carry out any pooled analyses. We assessed the quality of the evidence using GRADE and created a 'Summary of findings' table.

MAIN RESULTS

Three studies in adults satisfied the inclusion criteria, lasting up to one week; 122 participants were randomised initially, and 95 completed treatment. We found no studies in children. One study was parallel-group, and two had a cross-over design. All used paracetamol as an add-on to established treatment with strong opioids (median daily morphine equivalent doses of 60 mg, 70 mg, and 225 mg, with some participants taking several hundred mg of oral morphine equivalents daily). Other non-paracetamol medication included non-steroidal anti-inflammatory drugs (NSAIDs), tricyclic antidepressants, or neuroleptics. All studies were at high risk of bias for incomplete outcome data and small size; none was unequivocally at low risk of bias.None of the studies reported any of our primary outcomes: participants with pain reduction of at least 50%, and at least 30%, from baseline; participants with pain no worse than mild at the end of the treatment period; participants with Patient Global Impression of Change (PGIC) of much improved or very much improved (or equivalent wording). What pain reports there were indicated no difference between paracetamol and placebo when added to another treatment. There was no convincing evidence of paracetamol being different from placebo with regards to quality of life, use of rescue medication, or participant satisfaction or preference. Measures of harm (serious adverse events, other adverse events, and withdrawal due to lack of efficacy) were inconsistently reported and provided no clear evidence of difference.Our GRADE assessment of evidence quality was very low for all outcomes, because studies were at high risk of bias from several sources.

AUTHORS' CONCLUSIONS

There is no high-quality evidence to support or refute the use of paracetamol alone or in combination with opioids for the first two steps of the three-step WHO cancer pain ladder. It is not clear whether any additional analgesic benefit of paracetamol could be detected in the available studies, in view of the doses of opioids used.

Single dose oral ketoprofen or dexketoprofen for acute postoperative pain in adults

BACKGROUND

This review is an update of "Single dose oral ketoprofen and dexketoprofen for acute postoperative pain in adults" last updated in Issue 4, 2009. Ketoprofen is a non-selective nonsteroidal anti-inflammatory drug (NSAID) used to treat acute and chronic painful conditions. Dexketoprofen is the (S)-enantiomer, which is believed to confer analgesia. Theoretically dexketoprofen is expected to provide equivalent analgesia to ketoprofen at half the dose, with a consequent reduction in gastrointestinal adverse events. This review is one of a series on oral analgesics for acute postoperative pain. Individual reviews have been brought together in two overviews to provide information about the relative efficacy and harm of the different interventions.

OBJECTIVES

To assess the efficacy and safety of single dose oral ketoprofen and oral dexketoprofen compared with placebo for acute postoperative pain, using methods that permit comparison with other analgesics evaluated in the same way, and criteria of efficacy recommended by an in-depth study at the individual patient level.

SEARCH METHODS

For this update, we searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, and Embase from 2009 to 28 March 2017. We also searched the reference lists of retrieved studies and reviews, and two online clinical trial registries.

SELECTION CRITERIA

Randomised, double-blind, placebo-controlled trials of single dose orally administered ketoprofen or dexketoprofen in adults with moderate to severe acute postoperative pain.

DATA COLLECTION AND ANALYSIS

Two review authors independently considered studies for inclusion in the review, examined issues of study quality and potential bias, and extracted data. For dichotomous outcomes, we calculated risk ratio (RR) and number needed to treat for an additional beneficial outcome (NNT) or harmful outcome (NNH) with 95% confidence intervals (CI) for ketoprofen and dexketoprofen, compared with placebo, where there were sufficient data. We collected information on the number of participants with at least 50% of the maximum possible pain relief over six hours, the median time to use of rescue medication, and the proportion of participants requiring rescue medication. We also collected information on adverse events and withdrawals. We assessed the quality of the evidence using GRADE, and created 'Summary of findings' tables.

MAIN RESULTS

This updated review included 24 studies; six additional studies added 1001 participants involved in comparisons of ketoprofen or dexketoprofen and placebo, with a 12% increase in participants taking ketoprofen and a 65% increase for dexketoprofen. Most participants (70%) were women. Dental studies typically involved young participants (mean age 20 to 30 years); other types of surgery involved older participants (mean age 37 to 68 years). Overall, we judged the studies at high risk of bias only for small size, which can lead to an overestimation of benefit.Ketoprofen doses ranged between 6.5 mg and 150 mg. The proportion of participants achieving at least 50% pain relief over six hours with the usual ketoprofen oral dose of 50 mg was 57%, compared to 23% with placebo, giving an NNT of 2.9 (95% CI 2.4 to 3.7) (RR 2.5, 95% CI 2.0 to 3.1; 594 participants; 8 studies; high quality evidence). Efficacy was significantly better in dental studies (NNT 1.8) than other surgery (NNT 4.2). The proportion of participants using rescue medication within six hours was lower with ketoprofen (32%) than with placebo (75%), giving a number needed to treat to prevent use of rescue medication (NNTp) of 2.3 (95% CI 1.8 to 3.1); 263 participants; 4 studies; high quality evidence). Median time to remedication estimates were poorly reported. Reports of any adverse event were similar with ketoprofen (18%) and placebo (11%) (RR 1.6, 95% CI 0.98 to 2.8; 342 participants; 5 studies; high quality evidence). No study reported any serious adverse events (very low quality evidence).Dexketoprofen doses ranged between 5 mg and 100 mg. The proportion of participants achieving at least 50% pain relief over six hours with the usual dexketoprofen oral dose of 20 mg or 25 mg was 52%, compared to 27% with placebo, giving an NNT of 4.1 (95% CI 3.3 to 5.2) (RR 2.0, 95% CI 1.6 to 2.2; 1177 participants; 8 studies; high quality evidence). Efficacy was significantly better in dental studies (NNT 2.7) than other surgery (NNT 5.7). The proportion of participants using rescue medication within six hours was lower with dexketoprofen (47%) than placebo (69%), giving an NNTp of 4.7 (95% CI 3.3 to 8.0); 445 participants; 5 studies; high quality evidence). Median time to remedication estimates were poorly reported. Reports of any adverse event were similar with dexketoprofen (14%) and placebo (10%) (RR 1.4, 95% CI 0.89 to 2.2; 536 participants, 6 studies; high quality evidence). No study reported any serious adverse events (very low quality evidence).

AUTHORS' CONCLUSIONS

Ketoprofen at doses of 25 mg to 100 mg is an effective analgesic in moderate to severe acute postoperative pain with an NNT for at least 50% pain relief of 2.9 with a 50 mg dose. This is similar to that of commonly used NSAIDs such as ibuprofen (NNT 2.5 for 400 mg dose) and diclofenac (NNT 2.7 for 50 mg dose). Dexketoprofen is also effective with an NNT of 4.1 in the dose range 10 mg to 25 mg. Differential efficacy between dental surgery and other types of surgery seen for both drugs is unusual. Both drugs were well tolerated in single doses.

Factors associated with efficacy of an ibuprofen/pseudoephedrine combination drug in pharmacy customers with common cold symptoms

AIM

The aim of this study was to explore factors affecting efficacy of treatment of common cold symptoms with an over-the-counter ibuprofen/pseudoephedrine combination product.

METHODS

Data from an anonymous survey among 1770 pharmacy customers purchasing the combination product for treatment of own common cold symptoms underwent post-hoc descriptive analysis. Scores of symptoms typically responsive to ibuprofen (headache, pharyngeal pain, joint pain and fever), typically responsive to pseudoephedrine (congested nose, congested sinus and runny nose), considered non-specific (sneezing, fatigue, dry cough, cough with expectoration) and comprising all 11 symptoms were analysed. Multiple regression analysis was applied to explore factors associated with greater reduction in symptom intensity or greater probability of experiencing a symptom reduction of at least 50%.

RESULTS

After intake of first dose of medication, typically ibuprofen-sensitive, pseudoephedrine-responsive, non-specific and total symptoms were reduced by 60.0%, 46.3%, 45.4% and 52.8%, respectively. A symptom reduction of at least 50% was reported by 73.6%, 55.1%, 50.9% and 61.6% of participants, respectively. A high baseline score was associated with greater reductions in symptom scores but smaller probability of achieving an improvement of at least 50%. Across both multiple regression approaches, two tablets at first dosing were more effective than one and (except for ibuprofen-sensitive symptoms) starting treatment later than day 2 of the cold was generally less effective.

DISCUSSION AND CONCLUSIONS

Efficacy of an ibuprofen/pseudoephedrine combination in the treatment of common cold symptoms was dose-dependent and greatest when treatment started within the first 2 days after onset of symptoms.

Paracetamol (acetaminophen) for acute treatment of episodic tension-type headache in adults

BACKGROUND

Tension-type headache (TTH) affects about 1 person in 5 worldwide. It is divided into infrequent episodic TTH (fewer than one headache per month), frequent episodic TTH (two to 14 headaches per month), and chronic TTH (15 headache days a month or more). Paracetamol (acetaminophen) is one of a number of analgesics suggested for acute treatment of headaches in frequent episodic TTH.

OBJECTIVES

To assess the efficacy and safety of paracetamol for the acute treatment of frequent episodic TTH in adults.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (CRSO), MEDLINE, EMBASE, and the Oxford Pain Relief Database to October 2015, and also reference lists of relevant published studies and reviews. We sought unpublished studies by asking personal contacts and searching online clinical trial registers and manufacturers' websites.

SELECTION CRITERIA

We included randomised, double-blind, placebo-controlled studies (parallel-group or cross-over) using oral paracetamol for symptomatic relief of an acute episode of TTH. Studies had to be prospective, with participants aged 18 years or over, and include at least 10 participants per treatment arm.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for inclusion and extracted data. We used the numbers of participants achieving each outcome to calculate the risk ratio (RR) and number needed to treat for one additional beneficial outcome (NNT) or one additional harmful outcome (NNH) for oral paracetamol compared to placebo or an active intervention for a range of outcomes, predominantly those recommended by the International Headache Society (IHS).We assessed the evidence using GRADE (Grading of Recommendations Assessment, Development and Evaluation) and created 'Summary of findings' tables.

MAIN RESULTS

We included 23 studies, all of which enrolled adults with frequent episodic TTH. Twelve studies used the IHS diagnostic criteria or similar, six used the older classification of the Ad Hoc Committee, and five did not describe specific diagnostic criteria but generally excluded participants with migraines. Participants had moderate or severe pain at the start of treatment. While 8079 people with TTH participated in these studies, the numbers available for any analysis were lower than this because outcomes were inconsistently reported and because many participants received active comparators.None of the included studies were at low risk of bias across all domains considered, although for most studies and domains this was likely to be due to inadequate reporting rather than poor methods. We judged five studies to be at high risk of bias for incomplete outcome reporting, and seven due to small size.For the IHS preferred outcome of being pain free at two hours the NNT for paracetamol 1000 mg compared with placebo was 22 (95% confidence interval (CI) 15 to 40) in eight studies (5890 participants; high quality evidence), with no significant difference from placebo at one hour. The NNT was 10 (7.9 to 14) for pain-free or mild pain at two hours in five studies (5238 participants; high quality evidence). The use of rescue medication was lower with paracetamol 1000 mg than with placebo, with an NNTp to prevent an event of 7.8 (6.0 to 11) in six studies (1856 participants; moderate quality evidence). On limited data, the efficacy of paracetamol 500 mg to 650 mg was not superior to placebo, and paracetamol 1000 mg was not different from either ketoprofen 25 mg or ibuprofen 400 mg (low quality evidence).Adverse events were not different between paracetamol 1000 mg and placebo (RR 1.1 (0.94 to 1.3); 5605 participants; 11 studies; high quality evidence). Studies reported no serious adverse events.The quality of the evidence using GRADE comparing paracetamol 1000 mg with placebo was moderate to high. Where evidence was downgraded it was because a minority of studies reported the outcome. For comparisons of paracetamol 500 mg to 650 mg with placebo, and of paracetamol 1000 mg with active comparators, we downgraded the evidence to low quality or very low quality because of the small number of studies and events.

AUTHORS' CONCLUSIONS

Paracetamol 1000 mg provided a small benefit in terms of being pain free at two hours for people with frequent episodic TTH who have an acute headache of moderate or severe intensity.

Comparison of the effects of treatment with celecoxib, loxoprofen, and acetaminophen on postoperative acute pain after arthroscopic knee surgery: A randomized, parallel-group trial

BACKGROUND

Selective cyclooxygenase-2 (COX-2) inhibitors, conventional non-selective nonsteroidal anti-inflammatory drugs (NSAIDs), and acetaminophen have been adopted for the relief of mild to moderate acute and chronic pain. However, it remains unclarified whether the therapeutic differences in pain sensation exist among these agents. The aim of this study was to compare the efficacy of different types of analgesic agents for postoperative acute pain management.

METHODS

A single-center, randomized, controlled study was performed in consecutive patients who underwent the second-look procedure with removal of internal fixation after anterior cruciate ligament reconstruction or arthroscopic meniscal repair/meniscectomy. Celecoxib (400 mg for the first dose and then 200 mg), loxoprofen (60 mg), or acetaminophen (600 mg) was orally administered from postoperative 3 h. The pain intensity on a 100-mm VAS scale and subjective assessment of therapeutic pain-relief were compared among these three treatment groups until postoperative 2 days. The acquired data were analyzed according to the per-protocol analysis principle.

RESULTS

A total of 432 patients were screened, and 160 were enrolled. The VAS score tended to decrease over time in all groups. There was a significant improvement in the pain score both at rest and on movement, and subjective impression in the celecoxib-treated group compared with acetaminophen at postoperative 2 days. On the other hand, loxoprofen resulted in the benefit only in the pain score at rest in comparison with acetaminophen. Any comparisons between celecoxib and loxoprofen showed insignificant differences throughout observations. No adverse effects were confirmed in each group.

CONCLUSIONS

These obtained findings in our dose setting conditions suggest that celecoxib and loxoprofen treatments were superior to acetaminophen in pain-relief, though the superiority of loxoprofen over acetaminophen was modest. Overall, selective COX-2 inhibitors including conventional NSAIDs seem to have a possible advantage in acute pain management of relatively less invasive surgery.

Single dose oral analgesics for acute postoperative pain in adults - an overview of Cochrane reviews

BACKGROUND

This is an updated version of the original Cochrane overview published in Issue 9, 2011. That overview considered both efficacy and adverse events, but adverse events are now dealt with in a separate overview.Thirty-nine Cochrane reviews of randomised trials have examined the analgesic efficacy of individual drug interventions in acute postoperative pain. This overview brings together the results of those individual reviews and assesses the reliability of available data.

OBJECTIVES

To summarise the efficacy of pharmaceutical interventions for acute pain in adults with at least moderate pain following surgery who have been given a single dose of oral analgesic.

METHODS

We identified systematic reviews in the Cochrane Database of Systematic Reviews in The Cochrane Library through a simple search strategy. All reviews were overseen by a single review group, had a standard title, and had as their primary outcome the number of participants with at least 50% pain relief over four to six hours compared with placebo. For individual reviews, we extracted the number needed to treat for an additional beneficial outcome (NNT) for this outcome for each drug/dose combination, and also the percentage of participants achieving at least 50% maximum pain relief, the mean of mean or median time to remedication, and the percentage of participants remedicating by six, eight, 12, or 24 hours. Where there was adequate information for pairs of drug and dose (at least 200 participants, in at least two studies), we defined the addition of four comparisons of typical size (400 participants in total) with zero effect as making the result potentially subject to publication bias and therefore unreliable.

MAIN RESULTS

The overview included 39 separate Cochrane Reviews with 41 analyses of single dose oral analgesics tested in acute postoperative pain models, with results from about 50,000 participants in approximately 460 individual studies. The individual reviews included only high-quality trials of standardised design, methods, and efficacy outcome reporting. No statistical comparison was undertaken.Reliable results (high quality information) were obtained for 53 pairs of drug and dose in painful postsurgical conditions; these included various fixed dose combinations, and fast acting formulations of some analgesics. NNTs varied from about 1.5 to 20 for at least 50% maximum pain relief over four to six hours compared with placebo. The proportion of participants achieving this level of benefit varied from about 30% to over 70%, and the time to remedication varied from two hours (placebo) to over 20 hours. Good (low) NNTs were obtained with ibuprofen 200 mg plus paracetamol (acetaminophen) 500 mg (NNT compared with placebo 1.6; 95% confidence interval 1.5 to 1.8), ibuprofen fast acting 200 mg (2.1; 1.9 to 2.3); ibuprofen 200 mg plus caffeine 100 mg (2.1; 1.9 to 3.1), diclofenac potassium 50 mg (2.1; 1.9 to 2.5), and etoricoxib 120 mg (1.8; 1.7 to 2.0). For comparison, ibuprofen acid 400 mg had an NNT of 2.5 (2.4 to 2.6). Not all participants had good pain relief and, for many pairs of drug and dose, 50% or more did not achieve at least 50% maximum pain relief over four to six hours.Long duration of action (eight hours or greater) was found for etoricoxib 120 mg, diflunisal 500 mg, paracetamol 650 mg plus oxycodone 10 mg, naproxen 500/550 mg, celecoxib 400 mg, and ibuprofen 400 mg plus paracetamol 1000 mg.There was no evidence of analgesic effect for aceclofenac 150 mg, aspirin 500 mg, and oxycodone 5 mg (low quality evidence). No trial data were available in reviews of acemetacin, meloxicam, nabumetone, nefopam, sulindac, tenoxicam, and tiaprofenic acid. Inadequate amounts of data were available for nine drugs and doses, and data potentially susceptible to publication bias for 13 drugs and doses (very low quality evidence).

AUTHORS' CONCLUSIONS

There is a wealth of reliable evidence on the analgesic efficacy of single dose oral analgesics. Fast acting formulations and fixed dose combinations of analgesics can produce good and often long-lasting analgesia at relatively low doses. There is also important information on drugs for which there are no data, inadequate data, or where results are unreliable due to susceptibility to publication bias. This should inform choices by professionals and consumers.

Caffeine as an analgesic adjuvant for acute pain in adults

BACKGROUND

This is an updated version of the original Cochrane review published in Issue 3, 2012. Caffeine has been added to common analgesics such as paracetamol, ibuprofen, and aspirin, in the belief that it enhances analgesic efficacy. Evidence to support this belief is limited and often based on invalid comparisons.

OBJECTIVES

To assess the relative efficacy of a single dose of an analgesic plus caffeine against the same dose of the analgesic alone, without restriction on the analgesic used or the pain condition studied. We also assessed serious adverse events.

SEARCH METHODS

We searched CENTRAL, MEDLINE, and EMBASE from inception to 28 August 2014, the Oxford Pain Relief Database, and also carried out Internet searches and contacted pharmaceutical companies known to have carried out trials that have not been published.

SELECTION CRITERIA

We included randomised, double-blind studies that compared a single dose of analgesic plus caffeine with the same dose of the analgesic alone in the treatment of acute pain.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the eligibility and quality of studies, and extracted data. Any disagreements or uncertainties were settled by discussion with a third review author. We sought any validated measure of analgesic efficacy, but particularly the number of participants experiencing at least 50% of the maximum possible pain relief over four to six hours, participants reporting a global evaluation of treatment of very good or excellent, or headache relief after two hours. We pooled comparable data to look for a statistically significant difference, and calculated numbers needed to treat to benefit (NNT) with caffeine. We also looked for any numerical superiority associated with the addition of caffeine, and information about any serious adverse events.

MAIN RESULTS

We identified no new studies with available results for this update. The earlier review included 20 studies (7238 participants) in valid comparisons, but because we used different outcomes for some headache studies, the number of participants in the analyses of the effects of caffeine is now 4262 when previously it was 5243. The studies were generally of good methodological quality, using standard designs and mostly standard scales of pain measurement, although many of those treating postoperative pain were small.Most studies used paracetamol or ibuprofen, with 100 mg to 130 mg caffeine, and the most common pain conditions studied were postoperative dental pain, postpartum pain, and headache. There was a small but statistically significant benefit with caffeine used at doses of 100 mg or more, which was not dependent on the pain condition or type of analgesic. About 5% to 10% more participants achieve a good level of pain relief (at least 50% of the maximum over four to six hours) with the addition of caffeine, giving a NNT of about 14 (high quality evidence).Most comparisons individually demonstrated numerical superiority with caffeine, but not statistical superiority. One serious adverse event was reported with caffeine, but was considered unrelated to any study medication.We know of the existence of around 25 additional studies with almost 12,500 participants for which data for analysis were not obtainable. The additional analgesic effect of caffeine remained statistically significant but clinically less important even if all the known missing data had no effect; the bulk of the unobtainable data are reported to have similar results as this review.

AUTHORS' CONCLUSIONS

The addition of caffeine (≥ 100 mg) to a standard dose of commonly used analgesics provides a small but important increase in the proportion of participants who experience a good level of pain relief.

Nonopioid Drugs in the Treatment of Cancer Pain

The WHO analgesic ladder for the treatment of cancer pain provides a three-step sequential approach for analgesic administration based on pain severity that has global applicability. Nonopioids were recommended for mild pain, with the addition of mild opioids for moderate pain and strong opioids for severe pain. Here, we review the evidence for the use of nonopioid analgesic agents in patients with cancer and describe the mode of action of the main drug classes. Evidence supports the use of anti-inflammatory drugs such as acetaminophen/paracetamol and nonsteroidal anti-inflammatory drugs (NSAIDs) for mild cancer pain. Adding an NSAID to an opioid for stronger cancer pain is efficacious, but the risk of long-term adverse effects has not been quantified. There is limited evidence to support using acetaminophen with stronger opioids. Corticosteroids have a specific role in spinal cord compression and brain metastases, where improved analgesia is a secondary benefit. There is limited evidence for adding corticosteroids to stronger opioids when pain control is the primary objective. Systematic reviews suggest a role for antidepressant and anticonvulsant medications for neuropathic pain, but there are methodologic issues with the available studies. Bisphosphonates improve pain in patients with bony metastases in some tumor types. Denosumab may delay worsening of pain compared with bisphosphonates. Larger studies of longer duration are required to address outstanding questions concerning the use of nonopioid analgesia for stronger cancer pain.

Validating speed of onset as a key component of good analgesic response in acute pain

Background

Previous analysis of a single data set in acute pain following third molar extraction demonstrated a strong relationship between the speed of reduction of pain intensity and overall pain relief, as well as need for additional analgesia.

Methods

Individual patient data analysis of a single randomized, double-blind trial of placebo, paracetamol 1000 mg, ibuprofen sodium 400 mg and ibuprofen-poloxamer 400 mg following third molar extraction. Visual analogue scale pain intensity (VASPI) and other measurements were made at baseline, every 5–45 min, and at 60, 90, 120, 180, 240, 300 and 360 min.

Results

Most patients produced consistent VASPI results over time. For placebo and paracetamol, few patients achieved low VASPI scores and maintained them. For both ibuprofen formulations, VASPI scores fell rapidly during the first hour and were then typically maintained until later re-medication. Analysis of all patients showed that rapid VASPI reduction in the first hour was strongly correlated with good overall pain relief (high total pain relief over 0–6 h), and with lesser need for additional analgesia within 6 h. Results for this analysis were in very good agreement with a previous analysis, validating the relationship between fast initial pain intensity reduction and overall good pain relief in this setting.

Conclusions

In acute pain following third molar extraction, faster acting analgesic formulations provide earlier onset of pain relief, better overall pain relief and a less frequent need for additional analgesia, indicating longer lasting pain relief.

[Caffeine in analgesics--myth or medicine?]

Caffeine as an analgesic adiuvant has been discussed for many years. In a recent Cochrane review based on 19 studies with a total of 7238 patients, caffeine enhanced the efficacy of paracetamol, ibuprofen or aspirin with a number needed to treat (NNT) of about 16, comparable to the effect of doubling the dose of the primary analgesic, reported by other authors. Analgesia by caffeine is best explained by antagonism at adenosine receptors. Recent studies confirmed a favourable tolerability profile of caffeine when consumed in "normal" quantities (e.g. 300 mg or about 3 cups of coffee per day), including possible cardiovascular risks, effects on bone density, and exposure in pregnancy. Beneficial effects are known,e.g.,in Parkinson's disease and liver cirrhosis and fibrosis. Caffeine remains an analgesic adiuvant with a favourable risk-benefit balance.

Towards a mechanism-based approach to pain management in osteoarthritis

Pain is the defining symptom of osteoarthritis (OA), yet available treatment options, of which NSAIDs are the most common, provide inadequate pain relief and are associated with serious health risks when used long term. Chronic pain pathways are subject to complex levels of control and modulation, both in the periphery and in the central nervous system. Ongoing clinical and basic research is uncovering how these pathways operate in OA. Indeed, clinical investigation into the types of pain associated with progressive OA, the presence of central sensitization, the correlation with structural changes in the joint, and the efficacy of novel analgesics affords new insights into the pathophysiology of OA pain. Moreover, studies in disease-specific animal models enable the unravelling of the cellular and molecular pathways involved. We expect that increased understanding of the mechanisms by which chronic OA-associated pain is generated and maintained will offer opportunities for targeting and improving the safety of analgesia. In addition, using clinical and genetic approaches, it might become possible to identify subsets of patients with pain of different pathophysiology, thus enabling a tailored approach to pain management.

Efficacy and speed of onset of pain relief of fast-dissolving paracetamol on postsurgical dental pain: two randomized, single-dose, double-blind, placebo-controlled clinical studies

BACKGROUND

Paracetamol (APAP), also known as acetaminophen, is the most commonly used over-the-counter analgesic for the treatment of mild-to-moderate pain. However, the speed of onset of pain relief is limited mainly to the standard, immediate-release formulation. Efficacy and speed of onset of pain relief are critical in acute pain situations such as postsurgical dental pain, because reducing pain can improve clinical outcome and reduce the risk of transition from acute pain to more chronic pain. Efficacy and rapid onset also reduce the risk of excessive dosing with the analgesic.

OBJECTIVE

We sought to investigate the dose-response efficacy and speed of onset of pain relief of a fast-dissolving APAP formulation compared with lower doses of APAP and placebo in dental patients after impacted third molar extraction.

METHODS

Two single-center, single-dose, randomized, placebo-controlled, double-blind, double-dummy, parallel-group studies (Study I and Study II) were conducted to evaluate the efficacy and speed of onset of pain relief of different doses of a fast-dissolving APAP tablet (FD-APAP), standard APAP, and placebo in patients with postsurgical dental pain following third molar extraction. In Study I, a single dose of FD-APAP 1000 mg, FD-APAP 500 mg, or placebo was given to 300 patients; in Study II, a single dose of FD-APAP 1000 mg, standard APAP 650 mg, or placebo was given to 401 patients. All 701 patients from both studies were included in the analysis and safety assessment.

RESULTS

FD-APAP 1000 mg demonstrated significantly greater effect compared with FD-APAP 500 mg, APAP 650 mg, and placebo for all efficacy measurements, including sum of pain relief and pain intensity difference, total pain relief, sum of pain intensity difference, pain intensity difference, and pain relief score during 6 hours after the dose. Onset of confirmed first perceptible relief in subjects treated with FD-APAP 1000 mg was 15 minutes, which was 32% and 25% significantly shorter than onset of pain relief of FD-APAP 500 mg (22 minutes) and standard APAP 650 mg (20 minutes), respectively. FD-APAP 500 mg and APAP 650 mg demonstrated efficacy over placebo for most of the measurements; however, their effects were significantly lower and lasted for a shorter period of time than for FD-APAP 1000 mg. All study treatments were well tolerated.

CONCLUSIONS

FD-APAP 1000 mg tablets demonstrated efficacy over placebo. Also, FD-APAP 1000 mg had significantly superior effect, faster onset, and longer duration of pain relief compared with FD-APAP 500 mg and APAP 650 mg tablets.

Faster, higher, stronger? Evidence for formulation and efficacy for ibuprofen in acute pain

A Cochrane review of ibuprofen in acute pain suggested that rapidly absorbed formulations of salts, or features to speed absorption, provided better analgesia than standard ibuprofen as the free acid. We examined several lines of evidence to investigate what benefit derived from fast-acting formulations. A systematic review of the kinetics of oral ibuprofen (30 studies, 1015 subjects) showed that median maximum plasma concentrations of fast-acting formulations occurred before 50 min (29-35 min for arginine, lysine, and sodium salts) compared with 90 min for standard formulations. An updated analysis of clinical trials (over 10,000 patients) showed that fast-acting formulations produced significantly better analgesia over 6h and fewer remedications than standard formulations in both indirect and direct comparisons. In dental studies, 200-mg fast-acting ibuprofen (number needed to treat 2.1; 95% confidence interval 1.9-2.4) was as effective as 400 mg standard ibuprofen (number needed to treat 2.4; 95% confidence interval 2.2-2.5), with faster onset of analgesia. Individual patient data analysis in dental pain demonstrated a strong correlation between more rapid reduction of pain intensity over 0-60 min and better pain relief over 0-6h. Rapid initial reduction of pain intensity was also linked with reduced need for remedication. Fast-acting formulations of ibuprofen demonstrated more rapid absorption, faster initial pain reduction, good overall analgesia in more patients at the same dose, and probably longer-lasting analgesia, but with no higher rate of patients reporting adverse events. Achieving a better analgesic effect with fast-acting nonsteroidal anti-inflammatory drug formulations has important implications for safety. Formulation chemistry is of potential importance for analgesics.

Paracetamol/acetaminophen (single administration) for perineal pain in the early postpartum period

BACKGROUND

Perineal pain is a common but poorly studied adverse outcome following childbirth. Pain may result from perineal trauma due to bruising, spontaneous tears, surgical incisions (episiotomies), or in association with operative births (ventouse or forceps assisted births).

OBJECTIVES

To determine the efficacy of a single administration of paracetamol (acetaminophen) systemic drugs used in the relief of acute postpartum perineal pain

SEARCH METHODS

We updated the search of the Cochrane Pregnancy and Childbirth Group's Trials Register on 6 November 2012.

SELECTION CRITERIA

Randomised controlled trials (RCTs) assessing paracetamol (acetaminophen) in a single dose compared with placebo for women with early postpartum perineal pain. We excluded quasi-RCTs and cross-over studies.

DATA COLLECTION AND ANALYSIS

Two review authors assessed each paper for inclusion and extracted data. One review author reviewed the decisions and confirmed calculations for pain relief scores.

MAIN RESULTS

We did not identify any new trials from the updated search so the results remain unchanged as follows.We have included 10 studies describing two dosages of paracetamol. Of these, five studies (526 women) assessed 500 mg to 650 mg and six studies (841 women) assessed 1000 mg of paracetamol. We chose to use random-effects meta-analyses because of the heterogeneity in dosage used. Studies were from the 1970s to the early 1990s, and there was insufficient information to assess the risk of bias adequately, hence the findings need to be interpreted within this context.More women experienced pain relief with paracetamol compared with placebo (average risk ratio (RR) 2.14, 95% confidence interval (CI) 1.59 to 2.89, 10 studies, 1279 women). In addition, there were significantly fewer women having additional pain relief with paracetamol compared with placebo (RR 0.34, 95% CI 0.21 to 0.55, eight studies, 1132 women). Both the 500 mg to 650 mg and 1000 mg doses were effective in providing more pain relief than placebo.Maternal and neonatal potential adverse drug effects were not assessed in any of the included studies. Indeed few secondary outcomes were assessed.

AUTHORS' CONCLUSIONS

More women experienced pain relief, and fewer had additional pain relief, with paracetamol compared with placebo, although potential adverse effects were not assessed and generally the quality of studies was unclear.

Clinically relevant pain relief with an ibuprofen-releasing foam dressing: results from a randomized, controlled, double-blind clinical trial in exuding, painful venous leg ulcers

The objective of this 6-week, 120-patient, double-blind, randomized, controlled trial was to investigate if a foam dressing with ibuprofen provided clinically relevant pain relief (PAR) for exuding, painful venous leg ulcers in comparison with a similar foam dressing without ibuprofen. Primary outcome parameter was PAR compared with baseline pain during the first 5 days of the investigation. PAR was registered by the patient morning and evening. Main end point was proportion of patients reporting a summed PAR score of at least 50% of the total maximum PAR (i.e., responders) and the corresponding number needed to treat (NNT). Wound-related parameters such as ulcer healing, ulcer area reduction, and peri-ulcer skin condition as well as adverse events were recorded during all 6 weeks of the investigation. PAR was significantly greater in the ibuprofen foam group than the comparator group (p = 0.0438). There were 34% responders in the ibuprofen foam group vs. 19% in the comparator group (NNT = 6.8). When evening data were analyzed separately to evaluate PAR over daytime, NNT was 5.3. Wound healing parameters and adverse events were comparable. In conclusion, in this study, the ibuprofen foam dressing provided clinically relevant PAR for patients with exuding, painful venous ulcers.

Comparison of two doses of ketoprofen to treat pain: a double-blind, randomized, noninferiority trial

The aim of our study was to compare the efficacy and safety of two doses of ketoprofen (200 mg vs. 300 mg/day) in ambulatory emergency patients with pain related to traumatic and nontraumatic bone and joint diseases. We tested the hypothesis that the efficacy of the lower dose was not lower than that of the higher dose in a double-blind, randomized, noninferiority trial. Patients included in the study were aged 18-65 years with closed benign trauma of the motor system or acute noninfectious rheumatologic conditions, with a resting pain intensity ≥3/10 on a numeric pain scale (NPS), requiring ketoprofen for 5 days. The main end-point was based on two efficacy co-criteria: (i) mean change from baseline of resting pain intensity at the end of the day over 5 days and (ii) total intake of concomitant analgesics. We included 409 patients: 200 in the 200-mg group and 209 in the 300-mg group. The mean change in pain intensity at rest (difference between groups: 0.0, 95% CI -0.4 to 0.4; P = 1.00) and in analgesic consumption (difference between groups: -0.6, 95% CI -1.9 to 0.6; P = 0.33) was not significantly different between the two groups, and the differences were lower than the predefined inferiority margins (0.5 and 1.5, respectively), thus demonstrating noninferiority. No significant difference was noted in the incidence of adverse events (21% vs. 20%, P = 0.71). The efficacy of the 200-mg daily dose of ketoprofen in relieving pain in emergency cases was not inferior to that of the 300-mg dose.