Single dose oral codeine, as a single agent, for acute postoperative pain in adults

Evaluation and Treatment of Acute Trauma Pain in Older Adults

In the context of an ageing population, the demographic sands of trauma are shifting. Increasingly, trauma units are serving older adults who have sustained injuries in low-energy falls from a standing height. Older age is commonly associated with changes in physiology, as well as an increased prevalence of frailty and multimorbidity, including cardiac, renal and liver disease. These factors can complicate the safe and effective administration of analgesia in the older trauma patient. Trauma services therefore need to adapt to meet this demographic shift and ensure that trauma clinicians are sufficiently skilled in treating pain in complex older people. This article is dedicated to the management of acute trauma pain in older adults. It aims to highlight the notable clinical challenges of managing older trauma patients compared with their younger counterparts. It offers an overview of the evidence and practical opinion on the merits and drawbacks of commonly used analgesics, as well as more novel and emerging analgesic adjuncts. A search of Medline (Ovid, from inception to 7 November 2022) was conducted by a medical librarian to identify relevant articles using keyword and subject heading terms for trauma, pain, older adults and analgesics. Results were limited to articles published in the last 10 years and English language. Relevant articles' references were hand-screened to identify other relevant articles. There is paucity of dedicated high-quality evidence to guide management of trauma-related pain in older adults. Ageing-related changes in physiology, the accumulation of multimorbidity, frailty and the risk of inducing delirium secondary to analgesic medication present a suite of challenges in the older trauma patient. An important nuance of treating pain in older trauma patients is the challenge of balancing iatrogenic adverse effects of analgesia against the harms of undertreated pain, the complications and consequences of which include immobility, pneumonia, sarcopenia, pressure ulcers, long-term functional decline, increased long-term care needs and mortality. In this article, the role of non-opioid agents including short-course non-steroidal anti-inflammatory drugs (NSAIDs) is discussed. Opioid selection and dosing are reviewed for older adults suffering from acute trauma pain in the context of kidney and liver disease. The evidence base and limitations of other adjuncts such as topical and intravenous lidocaine, ketamine and regional anaesthesia in acute geriatric trauma are discussed.

Single-dose intravenous ibuprofen for acute postoperative pain in adults

BACKGROUND

Postoperative administration of non-steroidal anti-inflammatory drugs (NSAIDs) reduces patient opioid requirements and, in turn, may reduce the incidence and severity of opioid-induced adverse events (AEs).

OBJECTIVES

To assess the analgesic efficacy and adverse effects of single-dose intravenous (IV) ibuprofen, compared with placebo or an active comparator, for moderate-to-severe postoperative pain in adults.

SEARCH METHODS

We searched the following databases without language restrictions: CENTRAL, MEDLINE, Embase and LILACS on 10 June 2021. We checked clinical trials registers and reference lists of retrieved articles for additional studies.

SELECTION CRITERIA

We included randomized trials that compared a single postoperative dose of intravenous (IV) ibuprofen with placebo or another active treatment, for treating acute postoperative pain in adults following any surgery.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Two review authors independently considered trials for review inclusion, assessed risk of bias, and extracted data. Our primary outcome was the number of participants in each arm achieving at least 50% pain relief over a 4- and 6-hour period. Our secondary outcomes were time to, and number of participants using rescue medication; withdrawals due to lack of efficacy, adverse events (AEs), and for any other cause; and number of participants reporting or experiencing any AE, serious AEs (SAEs), and specific NSAID-related or opioid-related AEs. We were not able to carry out any planned meta-analysis. We assessed the certainty of the evidence using GRADE.

MAIN RESULTS

Only one study met our inclusion criteria, involving 201 total participants, mostly female (mean age 42 years), undergoing primary, unilateral, distal, first metatarsal bunionectomy (with osteotomy and internal fixation). Ibuprofen 300 mg, placebo or acetaminophen 1000 mg was administered intravenously to participants reporting moderate pain intensity the day after surgery. Since we identified only one study for inclusion, we did not perform any quantitative analyses. The study was at low risk of bias for most domains. We downgraded the certainty of the evidence due to serious study limitations, indirectness and imprecision. Ibuprofen versus placebo Findings of the single study found that at both the 4-hour and 6-hour assessment period, the proportion of participants with at least 50% pain relief was 32% (24/76) for those assigned to ibuprofen and 22% (11/50) for those assigned to placebo. These findings produced a risk ratio (RR) of 1.44 (95% confidence interval (CI) 0.77 to 2.66 versus placebo for at least 50% of maximum pain relief over the 4-hour and 6-hour period (very low-certainty evidence). Median time to rescue medication was 101 minutes for ibuprofen and 71 minutes for placebo (1 study, 126 participants; very low-certainty evidence). The number of participants using rescue medication was not reported within the included study. During the study (1 study, 126 participants), 58/76 (76%) of participants assigned to ibuprofen and 39/50 (78%) assigned to placebo reported or experienced any adverse event (AE), (RR 0.98, 95% CI 0.81 to 1.19; low-certainty evidence). No serious AEs (SAEs) were experienced (1 study, 126 participants; very low-certainty evidence). Ibuprofen versus active comparators Ibuprofen (300 mg) was similar to the active comparator, IV acetaminophen (1000 mg) at 4 hours and 6 hours (1 study, 126 participants). For those assigned to active control (acetaminophen), the proportion of participants with at least 50% pain relief was 35% (26/75) at 4 hours and 31% (23/75) at 6 hours. At 4 hours, these findings produced a RR of 0.91 (95% CI 0.58 to 1.43; very low-certainty evidence) versus active comparator (acetaminophen). At 6 hours, these findings produced a RR of 1.03 (95% CI 0.64 to 1.66; very low-certainty evidence) versus active comparator (acetaminophen). Median time to rescue medication was 101 minutes for ibuprofen and 125 minutes for the active comparator, acetaminophen (1 study, 151 participants; very low-certainty evidence). The number of participants using rescue medication was not reported within the included study. During the study, 8/76 (76%) of participants assigned to ibuprofen and 45/75 (60%) assigned to active control (acetaminophen) reported or experienced any AE, (RR 1.27, 95% CI 1.02 to 1.59; very low-certainty evidence). No SAEs were experienced (1 study, 151 participants; very low-certainty evidence).

AUTHORS' CONCLUSIONS

There is insufficient evidence to support or refute the suggestion that IV ibuprofen is effective and safe for acute postoperative pain in adults.

Spontaneous, Voluntary, and Affective Behaviours in Rat Models of Pathological Pain

In pain patients affective and motivational reactions as well as impairment of daily life activities dominate the clinical picture. In contrast, many rodent pain models have been established on the basis of mechanical hypersensitivity testing. Up to today most rodent studies on pain still rely on reflexive withdrawal responses only. This discrepancy has likely contributed to the low predictive power of preclinical pain models for novel therapies. Here, we used a behavioural test array for rats to behaviourally evaluate five aetiologically distinct pain models consisting of inflammatory-, postsurgical-, cephalic-, neuropathic- and chemotherapy-induced pain. We assessed paralleling clinical expressions and comorbidities of chronic pain with an array of behavioural tests to assess anxiety, social interaction, distress, depression, and voluntary/spontaneous behaviours. Pharmacological treatment of the distinct pain conditions was performed with pathology-specific and clinically efficacious analgesics as gabapentin, sumatriptan, naproxen, and codeine. We found that rats differed in their manifestation of symptoms depending on the pain model and that pathology-specific analgesics also reduced the associated behavioural parameters. Based on all behavioural test performed, we screened for tests that can discriminate experimental groups on the basis of reflexive as well as non-sensory, affective parameters. Together, we propose a set of non-evoked behaviours with a comparable predictive power to mechanical threshold testing for each pain model.

Single-dose intravenous ketorolac for acute postoperative pain in adults

BACKGROUND

Postoperative pain is common and may be severe. Postoperative administration of non-steroidal anti-inflammatory drugs (NSAIDs) reduces patient opioid requirements and, in turn, may reduce the incidence and severity of opioid-induced adverse events (AEs).

OBJECTIVES

To assess the analgesic efficacy and adverse effects of single-dose intravenous ketorolac, compared with placebo or an active comparator, for moderate to severe postoperative pain in adults.

SEARCH METHODS

We searched the following databases without language restrictions: CENTRAL, MEDLINE, Embase and LILACS on 20 April 2020. We checked clinical trials registers and reference lists of retrieved articles for additional studies.

SELECTION CRITERIA

Randomized double-blind trials that compared a single postoperative dose of intravenous ketorolac with placebo or another active treatment, for treating acute postoperative pain in adults following any surgery.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane.  Our primary outcome was the number of participants in each arm achieving at least 50% pain relief over a four- and six-hour period. Our secondary outcomes were time to and number of participants using rescue medication; withdrawals due to lack of efficacy, adverse events (AEs), and for any other cause; and number of participants experiencing any AE, serious AEs (SAEs), and NSAID-related or opioid-related AEs. For subgroup analysis, we planned to analyze different doses of parenteral ketorolac separately and to analyze results based on the type of surgery performed. We assessed the certainty of evidence using GRADE.

MAIN RESULTS

We included 12 studies, involving 1905 participants undergoing various surgeries (pelvic/abdominal, dental, and orthopedic), with 17 to 83 participants receiving intravenous ketorolac in each study. Mean study population ages ranged from 22.5 years to 67.4 years. Most studies administered a dose of ketorolac of 30 mg; one study assessed 15 mg, and another administered 60 mg. Most studies had an unclear risk of bias for some domains, particularly allocation concealment and blinding, and a high risk of bias due to small sample size. The overall certainty of evidence for each outcome ranged from very low to moderate. Reasons for downgrading certainty included serious study limitations, inconsistency and imprecision. Ketorolac versus placebo Very low-certainty evidence from eight studies (658 participants) suggests that ketorolac results in a large increase in the number of participants achieving at least 50% pain relief over four hours compared to placebo, but the evidence is very uncertain (risk ratio (RR) 2.81, 95% confidence interval (CI) 1.80 to 4.37). The number needed to treat for one additional participant to benefit (NNTB) was 2.4 (95% CI 1.8 to 3.7). Low-certainty evidence from 10 studies (914 participants) demonstrates that ketorolac may result in a large increase in the number of participants achieving at least 50% pain relief over six hours compared to placebo (RR 3.26, 95% CI 1.93 to 5.51). The NNTB was 2.5 (95% CI 1.9 to 3.7). Among secondary outcomes, for time to rescue medication, moderate-certainty evidence comparing intravenous ketorolac versus placebo demonstrated a mean median of 271 minutes for ketorolac versus 104 minutes for placebo (6 studies, 633 participants). For the number of participants using rescue medication, very low-certainty evidence from five studies (417 participants) compared ketorolac with placebo. The RR was 0.60 (95% CI 0.36 to 1.00), that is, it did not demonstrate a difference between groups. Ketorolac probably results in a slight increase in total adverse event rates compared with placebo (74% versus 65%; 8 studies, 810 participants; RR 1.09, 95% CI 1.00 to 1.19; number needed to treat for an additional harmful event (NNTH) 16.7, 95% CI 8.3 to infinite, moderate-certainty evidence). Serious AEs were rare. Low-certainty evidence from eight studies (703 participants) did not demonstrate a difference in rates between ketorolac and placebo (RR 0.62, 95% CI 0.13 to 3.03). Ketorolac versus NSAIDs  Ketorolac was compared to parecoxib in four studies and diclofenac in two studies. For our primary outcome, over both four and six hours there was no evidence of a difference between intravenous ketorolac and another NSAID (low-certainty and moderate-certainty evidence, respectively). Over four hours, four studies (337 participants) produced an RR of 1.04 (95% CI 0.89 to 1.21) and over six hours, six studies (603 participants) produced an RR of 1.06 (95% CI 0.95 to 1.19). For time to rescue medication, low-certainty evidence from four studies (427 participants) suggested that participants receiving ketorolac waited an extra 35 minutes (mean median 331 minutes versus 296 minutes). For the number of participants using rescue medication, very low-certainty evidence from three studies (260 participants) compared ketorolac with another NSAID. The RR was 0.90 (95% CI 0.58 to 1.40), that is, there may be little or no difference between groups.   Ketorolac probably results in a slight increase in total adverse event rates compared with another NSAID (76% versus 68%, 5 studies, 516 participants; RR 1.11, 95% CI 1.00 to 1.23; NNTH 12.5, 95% CI 6.7 to infinite, moderate-certainty evidence). Serious AEs were rare. Low-certainty evidence from five studies (530 participants) did not demonstrate a difference in rates between ketorolac and another NSAID (RR 3.18, 95% CI 0.13 to 76.99). Only one of the five studies reported a single serious AE.

AUTHORS' CONCLUSIONS

The amount and certainty of evidence for the use of intravenous ketorolac as a treatment for postoperative pain varies across efficacy and safety outcomes and amongst comparators, from very low to moderate. The available evidence indicates that postoperative intravenous ketorolac administration may offer substantial pain relief for most patients, but further research may impact this estimate. Adverse events appear to occur at a slightly higher rate in comparison to placebo and to other NSAIDs. Insufficient information is available to assess whether intravenous ketorolac has a different rate of gastrointestinal or surgical-site bleeding, renal dysfunction, or cardiovascular events versus other NSAIDs. There was a lack of studies in cardiovascular surgeries and in elderly populations who may be at increased risk for adverse events.

Single‐dose intravenous ketorolac for acute postoperative pain in adults

This is a protocol for a Cochrane Review (Intervention). The objectives are as follows:

To assess the analgesic efficacy and adverse effects of single‐dose IV ketorolac, compared with placebo or an active comparator, for moderate‐to‐severe postoperative pain in adults.

Single-dose intravenous diclofenac for acute postoperative pain in adults

BACKGROUND

Postoperative administration of non-steroidal anti-inflammatory drugs (NSAIDs) reduces patient opioid requirements and, in turn, reduces the incidence and severity of opioid-induced adverse events (AEs).

OBJECTIVES

To assess the analgesic efficacy and adverse effects of single-dose intravenous diclofenac, compared with placebo or an active comparator, for moderate to severe postoperative pain in adults.

SEARCH METHODS

We searched the following databases without language restrictions: the Cochrane Central Register of Controlled Trials (Cochrane Register of Studies Online), MEDLINE, and Embase on 22 May 2018. We checked clinical trials registers and reference lists of retrieved articles for additional studies.

SELECTION CRITERIA

We included randomized trials that compared a single postoperative dose of intravenous diclofenac with placebo or another active treatment, for treating acute postoperative pain in adults following any surgery.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Two review authors independently considered trials for review inclusion, assessed risk of bias, and extracted data.Our primary outcome was the number of participants in each arm achieving at least 50% pain relief over a four- and six-hour period.Our secondary outcomes were time to, and number of participants using rescue medication; withdrawals due to lack of efficacy, AEs, and for any cause; and number of participants experiencing any AE, serious AEs (SAEs), and NSAID-related AEs. We performed a post hoc analysis of opioid-related AEs, to enable indirect comparisons with other analyses of postoperative analgesics.For subgroup analysis, we planned to analyze different doses and formulations of parenteral diclofenac separately.We assessed the overall quality of the evidence for each outcome using GRADE and created two 'Summary of findings' tables.

MAIN RESULTS

We included eight studies, involving 1756 participants undergoing various surgeries (dental, mixed minor, abdominal, and orthopedic), with 20 to 175 participants receiving intravenous diclofenac in each study. Mean study population ages ranged from 24.5 years to 54.5 years. Intravenous diclofenac doses varied among and within studies, ranging from 3.75 mg to 75 mg. Five studies assessed newer formulations of parenteral diclofenac that could be administered as an undiluted intravenous bolus. Most studies had an unclear risk of bias for several domains and a high risk of bias due to small sample size. The overall quality of evidence for each outcome was generally low for reasons including unclear risk of bias in studies, imprecision, and low event numbers.Primary outcomeThree studies (277 participants) produced a number needed to treat for an additional beneficial outcome (NNTB) for at least 50% of maximum pain relief versus placebo of 2.4 (95% confidence interval (CI) 1.9 to 3.1) over four hours (low-quality evidence). Four studies (436 participants) produced an NNTB of 3.8 versus placebo (95% CI 2.9 to 5.9) over six hours (low-quality evidence). No studies provided data for the comparison of intravenous diclofenac with another NSAID over four hours. At six hours there was no difference between intravenous diclofenac and another NSAID (low-quality evidence).Secondary outcomesFor secondary efficacy outcomes, intravenous diclofenac was generally superior to placebo and similar to other NSAIDs.For time to rescue medication, comparison of intravenous diclofenac versus placebo demonstrated a median of 226 minutes for diclofenac versus 80 minutes for placebo (5 studies, 542 participants, low-quality evidence). There were insufficient data for pooled analysis for comparisons of diclofenac with another NSAID (very low-quality evidence).For the number of participants using rescue medication, two studies (235 participants) compared diclofenac with placebo. The number needed to treat to prevent one additional harmful event (NNTp) (here, the need for rescue medication) compared with placebo was 3.0 (2.2 to 4.5, low-quality evidence). The comparison of diclofenac with another NSAID included only one study (98 participants). The NNTp was 4.5 (2.5 to 33) for ketorolac versus diclofenac (very low-quality evidence).The numbers of participants withdrawing were generally low and inconsistently reported (very low-quality evidence). Participant withdrawals were: 6% (8/140) diclofenac versus 5% (7/128) placebo, and 9% (8/87) diclofenac versus 7% (6/82) another NSAID for lack of efficacy; 2% (4/211) diclofenac versus 0% (0/198) placebo, and 3% (4/138) diclofenac versus 2% (2/129) another NSAID due to AEs; and 11% (21/191) diclofenac versus 17% (30/179) placebo, and 18% (21/118) diclofenac versus 15% (17/111) another NSAID for any cause.Overall adverse event rates were similar between intravenous diclofenac and placebo (71% in both groups, 2 studies, 296 participants) and between intravenous diclofenac and another NSAID (55% and 58%, respectively, 2 studies, 265 participants) (low-quality evidence for both comparisons). Serious and specific AEs were rare, preventing meta-analysis.There were sufficient data for a dose-effect analysis for our primary outcome for only one alternative dose, 18.75 mg. Analysis of the highest dose employed in each study demonstrated a relative benefit compared with placebo of 1.9 (1.4 to 2.4), whereas for the group receiving 18.75 mg, the relative benefit versus placebo was 1.6 (1.2 to 2.1, 2 studies). Compared to another NSAID, the high-dose analysis demonstrated a relative benefit of 0.9 (0.8 to 1.1), for the group receiving 18.75 mg, the relative benefit was 0.78 (0.65 to 0.93). For direct comparison of high dose versus 18.75 mg, the proportion of participants with at least 50% pain relief was 66% (90/137) for the high-dose arm versus 57% (77/135) in the low-dose arm. There were insufficient data for subgroup meta-analysis of different diclofenac formulations.

AUTHORS' CONCLUSIONS

The amount and quality of evidence for the use of intravenous diclofenac as a treatment for postoperative pain is low. The available evidence indicates that postoperative intravenous diclofenac administration offers good pain relief for the majority of patients, but further research may impact this estimate. Adverse events appear to occur at a similar rate to other NSAIDs. Insufficient information is available to assess whether intravenous diclofenac has a different rate of bleeding, renal dysfunction, or cardiovascular events versus other NSAIDs. There was insufficient information to evaluate the efficacy and safety of newer versus traditional formulations of intravenous diclofenac. There was a lack of studies in major and cardiovascular surgeries and in elderly populations, which may be at increased risk for adverse events.

Single dose intravenous diclofenac for acute postoperative pain in adults

This is a protocol for a Cochrane Review (Intervention). The objectives are as follows:

To assess the analgesic efficacy and adverse effects of a single dose of intravenous diclofenac, compared with placebo or an active comparator, for moderate to severe postoperative pain in adults.

Paracetamol (acetaminophen) with or without codeine or dihydrocodeine for neuropathic pain in adults

BACKGROUND

Paracetamol, either alone or in combination with codeine or dihydrocodeine, is commonly used to treat chronic neuropathic pain. This review sought evidence for efficacy and harm from randomised double-blind studies.

OBJECTIVES

To assess the analgesic efficacy and adverse events of paracetamol with or without codeine or dihydrocodeine for chronic neuropathic pain in adults.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, and Embase from inception to July 2016, together with reference lists of retrieved papers and reviews, and two online study registries.

SELECTION CRITERIA

We included randomised, double-blind studies of two weeks' duration or longer, comparing paracetamol, alone or in combination with codeine or dihydrocodeine, with placebo or another active treatment in chronic neuropathic pain.

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.

MAIN RESULTS

No study satisfied the inclusion criteria. Effects of interventions were not assessed as there were no included studies. We have only very low quality evidence and have no reliable indication of the likely effect.

AUTHORS' CONCLUSIONS

There is insufficient evidence to support or refute the suggestion that paracetamol alone, or in combination with codeine or dihydrocodeine, works in any neuropathic pain condition.

Abuse of over-the-counter medicines: a pharmacist's perspective

Self-care and self-medication practices are essential components of any health care systems. The use of over-the-counter (OTC) medications is a part of the self-medication process. The popularity of OTC medication use among patients may increase the abuse potential of OTC medications. With pharmacists being as accessible as they are, they are often the first line of contact for patients, and have the opportunity to educate and counsel patients on appropriate OTC medication use. The presence of a pharmacist ensures safe and effective use of OTC medications. Pharmacists can liaise with other health care providers in the management of self-care practices by patients. However, a pharmacist has traditionally been underutilized in this role. This article provides a brief review on OTC medications with abuse potential and the effect of self-medication on OTC medication abuse. This review further describes the barriers faced by pharmacists in OTC medication abuse management, given the increased potential of prescription-to-OTC switch in recent years. In addition, the potential for a behind-the-counter drug category to boost patient–pharmacist interaction was discussed. The current review supports the positive role played by pharmacists in the management of OTC medication abuse. This review adds to the knowledge base of the barriers faced by pharmacists to prevent OTC medication abuse while developing appropriate intervention strategies. By expanding the role of pharmacists, OTC medication abuse may be controlled more effectively, thereby providing better patient medication therapy management and outcomes.

Single fixed-dose oral dexketoprofen plus tramadol for acute postoperative pain in adults

BACKGROUND

Combining two different analgesics in fixed doses in a single tablet can provide better pain relief than either drug alone in acute pain. This appears to be broadly true across a range of different drug combinations, in postoperative pain and migraine headache. A new combination of dexketoprofen (a nonsteroidal anti-inflammatory drug) plus tramadol (an opioid) has been tested in acute postoperative pain conditions. It is not yet licensed for use. 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 analgesic efficacy and adverse effects of a single fixed-dose of oral dexketoprofen plus tramadol, compared with placebo, for moderate to severe postoperative pain in adults, using methods that permit comparison with other analgesics evaluated in standardised trials using almost identical methods and outcomes. A secondary objective was to compare the combination with the individual analgesics alone.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) via CRSO, MEDLINE via Ovid, and Embase via Ovid from inception to 31 May 2016. We also searched the reference lists of retrieved studies and reviews, and two online clinical trial registries.

SELECTION CRITERIA

Randomised, double-blind trials of oral dexketoprofen plus tramadol administered as a single oral dose, for the relief of acute postoperative pain in adults, and compared to placebo.

DATA COLLECTION AND ANALYSIS

Two review authors independently considered trials 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) for dexketoprofen plus tramadol, compared with placebo with 95% confidence intervals (CI). 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 a 'Summary of findings' table.We also collected information on the number of participants with at least 50% of the maximum possible pain relief over six hours for dexketoprofen alone and tramadol alone.

MAIN RESULTS

We included three studies with 1853 participants who had undergone surgical removal of impacted wisdom teeth, hip replacement, or hysterectomy. The overall risk of bias across the three included studies was low, with unclear risk of bias in relation to the size of the three studies. Two studies did not report all our prespecified outcomes, which limited the analyses we could do.The proportion of participants achieving at least 50% pain relief over six hours with dexketoprofen 25 mg plus tramadol 75 mg was 66%, compared to 32% with placebo, giving an NNT of 3.0 (95% CI 2.5 to 3.7) (RR 2.1 (95% CI 1.7 to 2.4); 748 participants; 3 studies) (moderate quality evidence). The response rate with dexketoprofen 25 mg alone was 53% (RR 1.3 (95% CI 1.1 to 1.4); 744 participants; 3 studies) and with tramadol alone was 45% (RR 1.5 (95% CI 1.3 to 1.7); 741 participants; 3 studies) (moderate quality evidence). We downgraded the evidence because of some inconsistency in the results.The median time to use of rescue medication could not be estimated exactly, but was probably eight hours or more, indicating a long duration of effect (moderate quality evidence). We downgraded the evidence because it was not possible to estimate the effect exactly in the two multiple dose studies, resulting in imprecision. Fewer participants used rescue medication with higher doses of active treatment (summary statistic not calculated; 123 participants; 1 study) (very low quality evidence). We downgraded the evidence because the data came from a single study with few participants and events.Adverse events and serious adverse events were not reported consistently for the single dose phase of the studies. In the single dose study, 11% of participants experienced adverse events with dexketoprofen 25 mg plus tramadol 75 mg, which were mostly mild or moderate nausea, vomiting, or dizziness, and typical with these medicines. Rates were lower with placebo and lower doses (very low quality evidence). We downgraded the evidence because the data came from a single study with few participants and events. Information on multiple dosing over three and five days supported a low event rate with the combination. Overall, rates were generally low in all treatment arms, as they were for withdrawals for adverse events or other reasons.

AUTHORS' CONCLUSIONS

A single oral dose of dexketoprofen 25 mg plus tramadol 75 mg provided good levels of pain relief with long duration of action to more people than placebo or the same dose of dexketoprofen or tramadol alone. The magnitude of the effect was similar to other good analgesics. Adverse event rates were low.There is modest uncertainty about the precision of the point estimate for efficacy, but the NNT of 3 is consistent with other analgesics considered effective and commonly used.

Non-prescription (OTC) oral analgesics for acute pain - an overview of Cochrane reviews

BACKGROUND

Non-prescription (over-the-counter, or OTC) analgesics (painkillers) are used frequently. They are available in various brands, package sizes, formulations, and dose. They can be used for a range of different types of pain, but this overview reports on how well they work for acute pain (pain of short duration, usually with rapid onset). Thirty-nine Cochrane reviews of randomised trials have examined the analgesic efficacy of individual drug interventions in acute postoperative pain.

OBJECTIVES

To examine published Cochrane reviews for information about the efficacy of pain medicines available without prescription using data from acute postoperative pain.

METHODS

We identified OTC analgesics available in the UK, Australia, Canada, and the USA by examining online pharmacy websites. We also included some analgesics (diclofenac potassium, dexketoprofen, dipyrone) of importance in parts of the world, but not currently available in these jurisdictions.We identified systematic reviews by searching the Cochrane Database of Systematic Reviews (CDSR) on 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 numbers of participants with at least 50% pain relief over four to six hours compared with placebo. From 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 calculated the success rate to achieve at least 50% of maximum pain relief. We also examined the number of participants experiencing any adverse event, and whether the incidence was different from placebo.

MAIN RESULTS

We found information on 21 different OTC analgesic drugs, doses, and formulations, using information from 10 Cochrane reviews, supplemented by information from one non-Cochrane review with additional information on ibuprofen formulations (high quality evidence). The lowest (best) NNT values were for combinations of ibuprofen plus paracetamol, with NNT values below 2. Analgesics with values close to 2 included fast acting formulations of ibuprofen 200 mg and 400 mg, ibuprofen 200 mg plus caffeine 100 mg, and diclofenac potassium 50 mg. Combinations of ibuprofen plus paracetamol had success rates of almost 70%, with dipyrone 500 mg, fast acting ibuprofen formulations 200 mg and 400 mg, ibuprofen 200 mg plus caffeine 100 mg, and diclofenac potassium 50 mg having success rates above 50%. Paracetamol and aspirin at various doses had NNT values of 3 or above, and success rates of 11% to 43%. We found no information on many of the commonly available low dose codeine combinations.The proportion of participants experiencing an adverse event were generally not different from placebo, except for aspirin 1000 mg and (barely) ibuprofen 200 mg plus caffeine 100 mg. For ibuprofen plus paracetamol, adverse event rates were lower than with placebo.

AUTHORS' CONCLUSIONS

There is a body of reliable evidence about the efficacy of some of the most commonly available drugs and doses widely available without prescription. The postoperative pain model is predominantly pain after third molar extraction, which is used as the industry model for everyday pain. The proportion of people with acute pain who get good pain relief with any of them ranges from around 70% at best to less than 20% at worst; low doses of some drugs in fast acting formulations were among the best. Adverse events were generally no different from placebo. Consumers can make an informed choice based on this knowledge, together with availability and price. Headache and migraine were not included in this overview.

Adverse events associated with single dose oral analgesics for acute postoperative pain in adults - an overview of Cochrane reviews

BACKGROUND

This is an update of a Cochrane overview published in Issue 9, 2011; that overview considered both efficacy and adverse events. This overview considers adverse events, with efficacy dealt with in a separate overview.Thirty-nine Cochrane reviews of randomised trials have examined the adverse events associated with individual drug interventions in acute postoperative pain. This overview brings together the results of those individual reviews.

OBJECTIVES

To provide an overview of adverse event rates associated with single-dose oral analgesics, compared with placebo, for acute postoperative pain in adults.

METHODS

We identified systematic reviews in The Cochrane Database of Systematic Reviews on The Cochrane Library through a simple search strategy. All reviews were overseen by a single review group. We extracted information related to participants experiencing any adverse event, and reports of serious adverse events, and deaths from the individual reviews.

MAIN RESULTS

Information was available from 39 Cochrane reviews for 41 different analgesics or analgesic combinations (51 drug/dose/formulations) tested in single oral doses in participants with moderate or severe postoperative pain. This involved around 350 unique studies involving about 35,000 participants. Most studies involved younger participants with pain following removal of molar teeth.For most nonsteroidal anti-inflammatory drugs (NSAIDs), paracetamol, and combinations not containing opioids, there were few examples where participants experienced significantly more or fewer adverse events than with placebo. For aspirin 1000 mg and diflunisal 1000 mg, opioids, or fixed-dose combination drugs containing opioids, participants typically experienced significantly more adverse events than with placebo. Studies of combinations of ibuprofen and paracetamol reported significantly fewer adverse events.Serious adverse events were rare, occurring a rate of about 1 in 3200 participants.Most reviews did not report specific adverse events.

AUTHORS' CONCLUSIONS

Despite ongoing problems with the measurement, recording, and reporting of adverse events in clinical trials and in systematic reviews, the large amount of information available for single oral doses of analgesics provides evidence that adverse events rates are generally similar with active drug and placebo in these circumstances, except at higher doses of some drugs, and in combinations including opioids.

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.

Single dose oral ibuprofen plus caffeine for acute postoperative pain in adults

BACKGROUND

There is good evidence that combining two different analgesics in fixed doses in a single tablet can provide better pain relief in acute pain and headache than either drug alone, and that the drug-specific benefits are essentially additive. This appears to be broadly true in postoperative pain and migraine headache across a range of different drug combinations, and when tested in the same and different trials. Adding caffeine to analgesics also increases the number of people obtaining good pain relief. Combinations of ibuprofen and caffeine are available without prescription in some parts of the world.

OBJECTIVES

To assess the analgesic efficacy and adverse effects of a single oral dose of ibuprofen plus caffeine for moderate to severe postoperative pain, using methods that permit comparison with other analgesics evaluated in standardised trials using almost identical methods and outcomes.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, the Oxford Pain Relief Database, two clinical trial registries, and the reference lists of articles. The date of the most recent search was 1 February 2015.

SELECTION CRITERIA

Randomised, double-blind, placebo- or active-controlled clinical trials of single dose oral ibuprofen plus caffeine for acute postoperative pain in adults.

DATA COLLECTION AND ANALYSIS

Two review authors independently considered trials for inclusion in the review, assessed risk of bias, and extracted data. We used the area under the pain relief versus time curve to derive the proportion of participants with at least 50% pain relief over six hours prescribed either ibuprofen plus caffeine or placebo. We calculated the risk ratio (RR) and number needed to treat to benefit (NNT). We used information on the use of rescue medication to calculate the proportion of participants requiring rescue medication and the weighted mean of the median time to use. We also collected information on adverse effects.

MAIN RESULTS

We identified five randomised, double-blind studies with 1501 participants, but only four had been published and had relevant outcome data. These four studies were of high quality, although two of the studies were small.Both ibuprofen 200 mg + caffeine 100 mg and ibuprofen 100 mg + caffeine 100 mg produced significantly more participants than placebo who achieved at least 50% of maximum pain relief over six hours, and both doses significantly reduced remedication rates (moderate quality evidence). For at least 50% of maximum pain relief, the NNT was 2.1 (95% confidence interval 1.8 to 2.5) for ibuprofen 200 mg + caffeine 100 mg (four studies, 334 participants) and 2.4 (1.9 to 3.1) for ibuprofen 100 mg + caffeine 100 mg (two studies, 200 participants) (moderate quality evidence). These values were close to those predicted by published models for combination analgesics in acute pain, and were supported by low (good) NNT values for prevention of remedication.Adverse event rates were low, and no sensible analysis was possible.

AUTHORS' CONCLUSIONS

For ibuprofen 200 mg + caffeine 100 mg particularly, the low NNT value is among the lowest (best) values for analgesics in this pain model. The combination is not commonly available, but can be probably be achieved by taking a single 200 mg ibuprofen tablet with a cup of modestly strong coffee or caffeine tablets. In principle, this can deliver good analgesia at lower doses of ibuprofen.

Single dose oral diclofenac for acute postoperative pain in adults

BACKGROUND

Diclofenac is a nonsteroidal anti-inflammatory drug, available as a potassium salt (immediate release) or sodium salt (enteric coated to suppress dissolution in the stomach). This review updates an earlier review published in the Cochrane Database of Systematic Reviews (Issue 2, 2009) entitled 'Single dose oral diclofenac for acute postoperative pain in adults'.

OBJECTIVES

To assess the analgesic efficacy and adverse effects of a single oral dose of diclofenac for moderate to severe postoperative pain, using methods that permit comparison with other analgesics evaluated in standardised trials using almost identical methods and outcomes.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, the Oxford Pain Relief Database, two clinical trial registries, and the reference lists of articles. The date of the most recent search was 9 March 2015.

SELECTION CRITERIA

Randomised, double-blind, placebo-controlled clinical trials of single dose, oral diclofenac (sodium or potassium) for acute postoperative pain in adults.

DATA COLLECTION AND ANALYSIS

Two review authors independently considered studies for inclusion in the review, assessed risk of bias, and extracted data. We used the area under the pain relief versus time curve to derive the proportion of participants with at least 50% pain relief over six hours prescribed either diclofenac or placebo. We calculated the risk ratio (RR) and number needed to treat to benefit (NNT). We used information on the use of rescue medication to calculate the proportion of participants requiring rescue medication and the weighted mean of the median time to use. We also collected information on adverse effects.

MAIN RESULTS

This update included three new studies, providing a 26% increase in participants in comparisons between diclofenac and placebo. We included 18 studies involving 3714 participants, 1902 treated with diclofenac and 1007 with placebo. This update has also changed the focus of the review, examining the effects of formulation in more detail than previously. This is a result of increased understanding of the importance of speed of onset in determining analgesic efficacy in acute pain.The largest body of information, for diclofenac potassium 50 mg, in seven studies, produced an NNT for at least 50% of maximum pain relief compared with placebo of 2.1 (95% confidence interval (CI) 1.9 to 2.5) (high quality evidence). There was a graded improvement in efficacy as doses rose from 25 mg to 100 mg, both for participants achieving at least 50% maximum pain relief, and for remedication within 6 to 8 hours. Fast-acting formulations (dispersible products, solutions, and softgel formulations) had a similar efficacy for a 50 mg dose, with an NNT of 2.4 (2.0 to 3.0). Diclofenac sodium in a small number of studies produced a lesser effect, with an NNT of 6.6 (4.1 to 17) for the 50 mg dose.Adverse event rates were low in these single dose studies, with no difference between diclofenac and placebo (moderate quality evidence).

AUTHORS' CONCLUSIONS

Diclofenac potassium provides good pain relief at 25 mg, 50 mg, and 100 mg doses. Diclofenac sodium has limited efficacy and should probably not be used in acute pain.

Single dose oral ibuprofen plus codeine for acute postoperative pain in adults

BACKGROUND

This is an update of the original Cochrane review published in Issue 3, 2013. There is good evidence that combining two different analgesics in fixed doses in a single tablet can provide better pain relief in acute pain and headache than either drug alone, and that the drug-specific effects are essentially additive. This appears to be broadly true in postoperative pain and migraine headache across a range of different drug combinations and when tested in the same and different trials. Some combinations of ibuprofen and codeine are available without prescription (but usually only from a pharmacy) where the dose of codeine is lower, and with a prescription when the dose of codeine is higher.Use of combination analgesics that contain codeine has been a source of some concern because of misuse from over-the-counter preparations.

OBJECTIVES

To assess the analgesic efficacy and adverse effects of a single oral dose of ibuprofen plus codeine for acute moderate-to-severe postoperative pain using methods that permit comparison with other analgesics evaluated in standardised trials using almost identical methods and outcomes.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, the Oxford Pain Relief Database, ClinicalTrials.gov, and the reference lists of articles. The date of the most recent search was 1 December 2014.

SELECTION CRITERIA

Randomised, double-blind, placebo- or active-controlled clinical trials of single dose oral ibuprofen plus codeine for acute postoperative pain in adults.

DATA COLLECTION AND ANALYSIS

Two review authors independently considered trials for inclusion in the review, assessed risk of bias, and extracted data. We used the area under the pain relief versus time curve to derive the proportion of participants prescribed ibuprofen plus codeine, placebo, or the same dose of ibuprofen alone with at least 50% pain relief over six hours, using validated equations. We calculated the risk ratio (RR) and number needed to treat to benefit (NNT). We used information on the use of rescue medication to calculate the proportion of participants requiring rescue medication and the weighted mean of the median time to use. We also collected information on adverse effects. Analyses were planned for different doses of ibuprofen and codeine, but especially for codeine where we set criteria for low (< 10 mg), medium (10 to 20 mg), and high (> 20 mg) doses.

MAIN RESULTS

Since the last version of this review no new studies were found. Information was available from six studies with 1342 participants, using a variety of doses of ibuprofen and codeine. In four studies (443 participants) using ibuprofen 400 mg plus codeine 25.6 mg to 60 mg (high dose codeine) 64% of participants had at least 50% maximum pain relief with the combination compared to 18% with placebo. The NNT was 2.2 (95% confidence interval 1.8 to 2.6) (high quality evidence). In three studies (204 participants) ibuprofen plus codeine (any dose) was better than the same dose of ibuprofen (69% versus 55%) but the result was barely significant with a relative benefit of 1.3 (1.01 to 1.6) (moderate quality evidence). In two studies (159 participants) ibuprofen plus codeine appeared to be better than the same dose of codeine alone (69% versus 33%), but no analysis was done. There was no difference between the combination and placebo in the reporting of adverse events in these acute studies (moderate quality evidence).

AUTHORS' CONCLUSIONS

The combination of ibuprofen 400 mg plus codeine 25.6 mg to 60 mg demonstrates good analgesic efficacy. Very limited data suggest that the combination is better than the same dose of either drug alone, and that similar numbers of people experience adverse events with the combination as with placebo.

Codeine, alone and with paracetamol (acetaminophen), for cancer pain

BACKGROUND

Pain is very common in patients with cancer. Opioid analgesics, including codeine, play a significant role in major guidelines on the management of cancer pain, particularly for mild to moderate pain. Codeine is widely available and inexpensive, which may make it a good choice, especially in low-resource settings. Its use is controversial, in part because codeine is not effective in a minority of patients who cannot convert it to its active metabolite (morphine), and also because of concerns about potential abuse, and safety in children.

OBJECTIVES

To determine the efficacy and safety of codeine used alone or in combination with paracetamol for relieving cancer pain.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; The Cochrane Library 2014, Issue 2), MEDLINE and EMBASE from inception to 5 March 2014, supplemented by searches of clinical trial registries and screening of the reference lists of the identified studies and reviews in the field.

SELECTION CRITERIA

We sought randomised, double-blind, controlled trials using single or multiple doses of codeine, with or without paracetamol, for the treatment of cancer pain. Trials could have either parallel or cross-over design, with at least 10 participants per treatment group. Studies in children or adults reporting on any type, grade, and stage of cancer were eligible. We accepted any formulation, dosage regimen, and route of administration of codeine, and both placebo and active controls.

DATA COLLECTION AND ANALYSIS

Two review authors independently read the titles and abstracts of all studies identified by the searches and excluded those that clearly did not meet the inclusion criteria. For the remaining studies, two authors read the full manuscripts and assessed them for inclusion. We resolved discrepancies between review authors by discussion. Included studies were described qualitatively, since no meta-analysis was possible because of the small amount of data identified, and clinical and methodological between-study heterogeneity.

MAIN RESULTS

We included 15 studies including 721 participants with cancer pain due to diverse types of malignancy. All studies were performed on adults; there were no studies on children. The included studies were of adequate methodological quality, but all except for one were judged to be at a high risk of bias because of small study size, and six because of methods used to deal with missing data or high withdrawal rates. Three studies used a parallel group design; the remainder were cross-over trials in which there was an adequate washout period, but only one reported results for treatment periods separately.Twelve studies used codeine as a single agent and three combined it with paracetamol. Ten studies included a placebo arm, and 14 included one or more of 16 different active drug comparators or compared different routes of administration. Most studies investigated the effect of a single dose of medication, while five used treatment periods of one, seven or 21 days. Most studies used codeine at doses of 30 mg to 120 mg.There were insufficient data for any pooled analysis. Only two studies reported our preferred responder outcome of 'participants with at least 50% reduction in pain' and two reported 'participants with no worse than mild pain'. Eleven studies reported treatment group mean measures of pain intensity or pain relief; overall for these outcome measures, codeine or codeine plus paracetamol was numerically superior to placebo and equivalent to the active comparators.Adverse event reporting was poor: only two studies reported the number of participants with any adverse event specified by treatment group and only one reported the number of participants with any serious adverse event. In multiple-dose studies nausea, vomiting and constipation were common, with somnolence and dizziness frequent in the 21-day study. Withdrawal from the studies, where reported, was less than 10% except in two studies. There were three deaths, in all cases due to the underlying cancer.

AUTHORS' CONCLUSIONS

We identified only a small amount of data in studies that were both randomised and double-blind. Studies were small, of short duration, and most had significant shortcomings in reporting. The available evidence indicates that codeine is more effective against cancer pain than placebo, but with increased risk of nausea, vomiting, and constipation. Uncertainty remains as to the magnitude and time-course of the analgesic effect and the safety and tolerability in longer-term use. There were no data for children.

Utility of the sore throat pain model in a multiple-dose assessment of the acute analgesic flurbiprofen: a randomized controlled study

BACKGROUND

The sore throat pain model has been conducted by different clinical investigators to demonstrate the efficacy of acute analgesic drugs in single-dose randomized clinical trials. The model used here was designed to study the multiple-dose safety and efficacy of lozenges containing flurbiprofen at 8.75 mg.

METHODS

Adults (n=198) with moderate or severe acute sore throat and findings of pharyngitis on a Tonsillo-Pharyngitis Assessment (TPA) were randomly assigned to use either flurbiprofen 8.75 mg lozenges (n=101) or matching placebo lozenges (n=97) under double-blind conditions. Patients sucked one lozenge every three to six hours as needed, up to five lozenges per day, and rated symptoms on 100-mm scales: the Sore Throat Pain Intensity Scale (STPIS), the Difficulty Swallowing Scale (DSS), and the Swollen Throat Scale (SwoTS).

RESULTS

Reductions in pain (lasting for three hours) and in difficulty swallowing and throat swelling (for four hours) were observed after a single dose of the flurbiprofen 8.75 mg lozenge (P<0.05 compared with placebo). After using multiple doses over 24 hours, flurbiprofen-treated patients experienced a 59% greater reduction in throat pain, 45% less difficulty swallowing, and 44% less throat swelling than placebo-treated patients (all P<0.01). There were no serious adverse events.

CONCLUSIONS

Utilizing the sore throat pain model with multiple doses over 24 hours, flurbiprofen 8.75 mg lozenges were shown to be an effective, well-tolerated treatment for sore throat pain. Other pharmacologic actions (reduced difficulty swallowing and reduced throat swelling) and overall patient satisfaction from the flurbiprofen lozenges were also demonstrated in this multiple-dose implementation of the sore throat pain model.

TRIAL REGISTRATION

This trial was registered with ClinicalTrials.gov, registration number: NCT01048866, registration date: January 13, 2010.

Single dose oral dexibuprofen [S(+)-ibuprofen] for acute postoperative pain in adults

BACKGROUND

This review is an update of a previously published review in The Cochrane Database of Systematic Reviews Issue 3, 2009 on single dose oral dexibuprofen (S(+)-ibuprofen) for acute postoperative pain in adults.Dexibuprofen is a non-steroidal anti-inflammatory drug (NSAID) licensed for use in rheumatic disease and other musculoskeletal disorders in the UK, and widely available in other countries worldwide. It is an active isomer of ibuprofen. This review sought to evaluate the efficacy and safety of oral dexibuprofen in acute postoperative pain, using clinical studies in patients with established pain, and with outcomes measured primarily over four to six hours, using standard methods. This type of study has been used for many decades to establish that drugs have analgesic properties.

OBJECTIVES

To assess the efficacy and adverse effects of single dose oral dexibuprofen for acute postoperative pain using methods that permit comparison with other analgesics evaluated in standardised studies using almost identical methods and outcomes.

SEARCH METHODS

Searches were run for the original review in 2009 and subsequent searches have been run in August 2013. We did not find any new published studies as a result of the updated search.We searched for randomised studies of dexibuprofen in acute postoperative pain in MEDLINE, EMBASE, and CENTRAL (The Cochrane LIbrary), and for clinical trial reports and synopses of published and unpublished studies from Internet sources.

SELECTION CRITERIA

Randomised, double blind, placebo-controlled clinical studies of oral dexibuprofen for relief of acute postoperative pain in adults.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed study quality and extracted data. We extracted pain relief or pain intensity data and converted it into the dichotomous outcome of number of participants with at least 50% pain relief over four to six hours, from which relative risk and number needed to treat to benefit (NNT) were calculated. Numbers of participants using rescue medication over specified time periods, and time to use of rescue medication, were sought as additional measures of efficacy. We collected information on adverse events and withdrawals.

MAIN RESULTS

New data were identified for this update in one unpublished trial synopsis (BR1160 1995) in addition to the single study (Dionne 1998) that was included in the original review. In both studies dexibuprofen gave high levels of response, with 51/96 (53%) participants experiencing at least 50% pain relief with dexibuprofen 200 mg and 35/50 (70%) with dexibuprofen 400 mg, compared with 75/147 (51%) with racemic ibuprofen 400 mg, and 12/62 (13%) with placebo. The numbers of participants was too small to calculate NNTs with any meaning. The median time to additional analgesic use was greater than four hours for all active therapies, but about two hours for placebo.Adverse events were generally of mild or moderate intensity and consistent with events normally associated with anaesthesia and surgery. There were no serious adverse events or deaths.Additional data did not alter the conclusions from the earlier review.

AUTHORS' CONCLUSIONS

The information from these two studies in acute postoperative pain suggested that dexibuprofen may be a useful analgesic, but at doses not very different from racemic ibuprofen, for which considerably more evidence exists.

Clinical pharmacology of analgesics assessed with human experimental pain models: bridging basic and clinical research

The medical impact of pain is such that much effort is being applied to develop novel analgesic drugs directed towards new targets and to investigate the analgesic efficacy of known drugs. Ongoing research requires cost-saving tools to translate basic science knowledge into clinically effective analgesic compounds. In this review we have re-examined the prediction of clinical analgesia by human experimental pain models as a basis for model selection in phase I studies. The overall prediction of analgesic efficacy or failure of a drug correlated well between experimental and clinical settings. However, correct model selection requires more detailed information about which model predicts a particular clinical pain condition. We hypothesized that if an analgesic drug was effective in an experimental pain model and also a specific clinical pain condition, then that model might be predictive for that particular condition and should be selected for development as an analgesic for that condition. The validity of the prediction increases with an increase in the numbers of analgesic drug classes for which this agreement was shown. From available evidence, only five clinical pain conditions were correctly predicted by seven different pain models for at least three different drugs. Most of these models combine a sensitization method. The analysis also identified several models with low impact with respect to their clinical translation. Thus, the presently identified agreements and non-agreements between analgesic effects on experimental and on clinical pain may serve as a solid basis to identify complex sets of human pain models that bridge basic science with clinical pain research.

Single dose oral ibuprofen plus oxycodone for acute postoperative pain in adults

BACKGROUND

Combining two different analgesics in fixed doses in a single tablet can provide better pain relief than either drug alone in acute pain. This appears to be broadly true across a range of different drug combinations, in postoperative pain and migraine headache. Fixed-dose combinations of ibuprofen and oxycodone are available, and the drugs may be separately used in combination in some acute pain situations.

OBJECTIVES

To assess the analgesic efficacy and adverse effects of a single oral dose of ibuprofen plus oxycodone for moderate to severe postoperative pain.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials, (CENTRAL), on The Cochrane Library, (Issue 4 of 12, 2013), MEDLINE (1950 to 21st May 2013), EMBASE (1974 to 21st May 2013), the Oxford Pain Database, ClinicalTrials.gov, and reference lists of articles.

SELECTION CRITERIA

Randomised, double-blind clinical trials of single dose, oral ibuprofen plus oxycodone compared with placebo or the same dose of ibuprofen alone for acute postoperative pain in adults.

DATA COLLECTION AND ANALYSIS

Two review authors independently considered trials for inclusion in the review, assessed quality, and extracted data. We used the area under the pain relief versus time curve to derive the proportion of participants prescribed ibuprofen plus oxycodone, ibuprofen alone, oxycodone alone, or placebo with at least 50% pain relief over six hours, using validated equations. We calculated relative risk (RR) and number needed to treat to benefit (NNT). We used information on use of rescue medication to calculate the proportion of participants requiring rescue medication and the weighted mean of the median time to use. We also collected information on adverse events.

MAIN RESULTS

Searches identified three studies involving 1202 participants. All examined the same dose combination. Included studies provided data from 603 participants for the comparison of ibuprofen 400 mg + oxycodone 5 mg with placebo, 717 participants for the comparison of ibuprofen 400 mg + oxycodone 5 mg with ibuprofen 400 mg alone, and 471 participants for the comparison of ibuprofen 400 mg + oxycodone 5 mg with oxycodone 5 mg alone.The proportion of participants achieving at least 50% pain relief over 6 hours was 60% with ibuprofen 400 mg + oxycodone 5 mg and 17% with placebo, giving an NNT of 2.3 (2.0 to 2.8). For ibuprofen 400 mg alone the proportion was 50%, producing no significant difference between ibuprofen 400 mg + oxycodone 5 mg and ibuprofen 400 mg alone. For oxycodone 5 mg alone the proportion was 23%, giving an NNT for ibuprofen 400 mg + oxycodone 5 mg compared with oxycodone alone of 2.9 (2.3 to 4.0).Ibuprofen + oxycodone resulted in longer times to remedication than with placebo. The median time to use of rescue medication was more than 5 hours for ibuprofen 400 mg + oxycodone 5 mg, and 2.3 hours or less with placebo. Fewer participants needed rescue medication with ibuprofen + oxycodone combination than with placebo or ibuprofen alone. The proportion was 40% with ibuprofen 400 mg + oxycodone 5 mg, 83% with placebo, 53% with ibuprofen alone, and 83% with oxycodone alone, giving NNT to prevent one patient needing rescue medication of 2.4 (2.0 to 2.9), 11 (6.1 to 56), and 2.6 (2.1 to 3.4) for comparisons of ibuprofen 400 mg + oxycodone 5 mg with placebo, ibuprofen alone, and oxycodone alone, respectively.The proportion of participants experiencing one or more adverse events was 25% with ibuprofen 400 mg + oxycodone 5 mg, 25% with placebo, 26% with ibuprofen alone, and 35% with oxycodone alone; they were not significantly different. Serious adverse events were reported only after abdominal surgery 6/169 with the combination, 1/175 with ibuprofen alone, 3/52 with oxycodone alone, and 1/60 with placebo. Withdrawals for reasons other than lack of efficacy were fewer than 5% and balanced across treatment arms.

AUTHORS' CONCLUSIONS

The combination of ibuprofen 400mg + oxycodone 5mg provided analgesia for longer than oxycodone alone, but not ibuprofen alone (at the same dose). There was also a smaller chance of needing additional analgesia over about eight hours, and with no greater chance of experiencing an adverse event.

Single dose oral ibuprofen plus paracetamol (acetaminophen) for acute postoperative pain

BACKGROUND

Combining two different analgesics in fixed doses in a single tablet can provide better pain relief than either drug alone in acute pain. This appears to be broadly true across a range of different drug combinations, in postoperative pain and migraine headache. Some combinations of ibuprofen and paracetamol are available for use without prescription in some acute pain situations.

OBJECTIVES

To assess the efficacy and adverse effects of single dose oral ibuprofen plus paracetamol for acute postoperative pain using methods that permit comparison with other analgesics evaluated in standardised trials using almost identical methods and outcomes.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) on The Cochrane Library (Issue 4 of 12, 2013), MEDLINE (1950 to May 21st 2013), EMBASE (1974 to May 21st 2013), the Oxford Pain Database, ClinicalTrials.gov, and reference lists of articles.

SELECTION CRITERIA

Randomised, double-blind clinical trials of single dose, oral ibuprofen plus paracetamol compared with placebo or the same dose of ibuprofen alone for acute postoperative pain in adults.

DATA COLLECTION AND ANALYSIS

Two review authors independently considered trials for inclusion in the review, assessed quality, and extracted data. We used validated equations to calculate the area under the pain relief versus time curve and derive the proportion of participants with at least 50% of maximum pain relief over six hours. We calculated relative risk (RR) and number needed to treat to benefit (NNT) for ibuprofen plus paracetamol, ibuprofen alone, or placebo. We used information on use of rescue medication to calculate the proportion of participants requiring rescue medication and the weighted mean of the median time to use. We also collected information on adverse events.

MAIN RESULTS

Searches identified three studies involving 1647 participants. Each of them examined several dose combinations. Included studies provided data from 508 participants for the comparison of ibuprofen 200 mg + paracetamol 500 mg with placebo, 543 participants for the comparison of ibuprofen 400 mg + paracetamol 1000 mg with placebo, and 359 participants for the comparison of ibuprofen 400 mg + paracetamol 1000 mg with ibuprofen 400 mg alone.The proportion of participants achieving at least 50% maximum pain relief over 6 hours was 69% with ibuprofen 200 mg + paracetamol 500 mg, 73% with ibuprofen 400 mg + paracetamol 1000 mg, and 7% with placebo, giving NNTs of 1.6 (1.5 to 1.8) and 1.5 (1.4 to 1.7) for the lower and higher doses respectively compared with placebo. For ibuprofen 400 mg alone the proportion was 52%, giving an NNT for ibuprofen 400 mg + paracetamol 1000 mg compared with ibuprofen alone of 5.4 (3.5 to 12).Ibuprofen + paracetamol at the 200/500 mg and 400/1000 mg doses resulted in longer times to remedication than placebo. The median time to use of rescue medication was 7.6 hours for ibuprofen 200 mg + paracetamol 500 mg, 8.3 hours with ibuprofen 400 mg + paracetamol 1000 mg, and 1.7 hours with placebo. Fewer participants needed rescue medication with ibuprofen + paracetamol combination than with placebo or ibuprofen alone. The proportion was 34% with ibuprofen 200 mg + paracetamol 500 mg, 25% with ibuprofen 400 mg + paracetamol 1000 mg, and 79% with placebo, giving NNTs to prevent use of rescue medication of 2.2 (1.8 to 2.9) and 1.8 (1.6 to 2.2) respectively compared with placebo. The proportion of participants using rescue medication with ibuprofen 400 mg was 48%, giving an NNT to prevent use for ibuprofen 400 mg + paracetamol 1000 mg compared with ibuprofen alone of 4.3 (3.0 to 7.7).The proportion of participants experiencing one or more adverse events was 30% with ibuprofen 200 mg + paracetamol 500 mg, 29% with ibuprofen 400 mg + paracetamol 1000 mg, and 48% with placebo, giving NNT values in favour of the combination treatment of 5.4 (3.6 to 10.5) and 5.1 (3.5 to 9.5) for the lower and higher doses respectively. No serious adverse events were reported in any of the included studies. Withdrawals for reasons other than lack of efficacy were fewer than 5% and balanced across treatment arms.

AUTHORS' CONCLUSIONS

Ibuprofen plus paracetamol combinations provided better analgesia than either drug alone (at the same dose), with a smaller chance of needing additional analgesia over about eight hours, and with a smaller chance of experiencing an adverse event.

Pharmacogenomic considerations in opioid analgesia

Translating pharmacogenetics to clinical practice has been particularly challenging in the context of pain, due to the complexity of this multifaceted phenotype and the overall subjective nature of pain perception and response to analgesia. Overall, numerous genes involved with the pharmacokinetics and dynamics of opioids response are candidate genes in the context of opioid analgesia. The clinical relevance of CYP2D6 genotyping to predict analgesic outcomes is still relatively unknown; the two extremes in CYP2D6 genotype (ultrarapid and poor metabolism) seem to predict pain response and/or adverse effects. Overall, the level of evidence linking genetic variability (CYP2D6 and CYP3A4) to oxycodone response and phenotype (altered biotransformation of oxycodone into oxymorphone and overall clearance of oxycodone and oxymorphone) is strong; however, there has been no randomized clinical trial on the benefits of genetic testing prior to oxycodone therapy. On the other hand, predicting the analgesic response to morphine based on pharmacogenetic testing is more complex; though there was hope that simple genetic testing would allow tailoring morphine doses to provide optimal analgesia, this is unlikely to occur. A variety of polymorphisms clearly influence pain perception and behavior in response to pain. However, the response to analgesics also differs depending on the pain modality and the potential for repeated noxious stimuli, the opioid prescribed, and even its route of administration.

Single dose oral analgesics for acute postoperative pain in adults

BACKGROUND

Thirty-five Cochrane Reviews of randomised trials testing the analgesic efficacy of individual drug interventions in acute postoperative pain have been published. This overview brings together the results of all those reviews and assesses the reliability of available data.

OBJECTIVES

To summarise data from all Cochrane Reviews that have assessed the effects 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 taken alone.

METHODS

We identified 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 numbers 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 (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, the percentage of participants remedicating by 6, 8, 12, or 24 hours, and results for participants experiencing at least one adverse event.

MAIN RESULTS

The overview included 35 separate Cochrane Reviews with 38 analyses of single dose oral analgesics tested in acute postoperative pain models, with results from about 45,000 participants studied in approximately 350 individual studies. The individual reviews included only high-quality trials of standardised design and outcome reporting. The reviews used standardised methods and reporting for both efficacy and harm. Event rates with placebo were consistent in larger data sets. No statistical comparison was undertaken.There were reviews but no trial data were available for acemetacin, meloxicam, nabumetone, nefopam, sulindac, tenoxicam, and tiaprofenic acid. Inadequate amounts of data were available for dexibuprofen, dextropropoxyphene 130 mg, diflunisal 125 mg, etoricoxib 60 mg, fenbufen, and indometacin. Where there was adequate information for drug/dose combinations (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. Reliable results were obtained for 46 drug/dose combinations in all painful postsurgical conditions; 45 in dental pain and 14 in other painful conditions.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 in the same pain condition. Participants reporting at least one adverse event were few and generally no different between active drug and placebo, with a few exceptions, principally for aspirin and opioids.Drug/dose combinations with good (low) NNTs were ibuprofen 400 mg (2.5; 95% confidence interval (CI) 2.4 to 2.6), diclofenac 50 mg (2.7; 95% CI 2.4 to 3.0), etoricoxib 120 mg (1.9; 95% CI 1.7 to 2.1), codeine 60 mg + paracetamol 1000 mg (2.2; 95% CI 1.8 to 2.9), celecoxib 400 mg (2.5; 95% CI 2.2 to 2.9), and naproxen 500/550 mg (2.7; 95% CI 2.3 to 3.3). Long duration of action (≥ 8 hours) was found for etoricoxib 120 mg, diflunisal 500 mg, oxycodone 10 mg + paracetamol 650 mg, naproxen 500/550 mg, and celecoxib 400 mg.Not all participants had good pain relief and for many drug/dose combinations 50% or more did not achieve at last 50% maximum pain relief over four to six hours.

AUTHORS' CONCLUSIONS

There is a wealth of reliable evidence on the analgesic efficacy of single dose oral analgesics. 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.