Single dose oral aspirin for acute postoperative pain in adults

Aspirin/PLGA coated 3D-printed Ti-6Al-4V alloy modulate macrophage polarization to enhance osteoblast differentiation and osseointegration

Although titanium (Ti) and Ti-based alloy have been widely used as dental and orthopedic implant materials, its bioinertness hindered the rapid osseointegration. Therefore, it is recommended to acquire ideal topographic and chemical characteristics through surface modification methods. 3D printing is a delicate manufacture technique which possesses superior controllability and reproducibility. While aspirin serve as a well-established non-steroidal anti-inflammatory agent. Recently, the importance of immune system in regulating bone dynamics has attracted increasing attention. We herein superimposed the aspirin/poly (lactic-co-glycolic acid) (ASP/PLGA) coating on the 3D-printed Ti-6Al-4V surface with uniform micro-structure to establish the Ti64-M-ASP/PLGA substrate. Scanning electron microscopy (SEM), x-ray photoelectron spectroscopy (XPS) and contact angle test confirmed the successful fabrication of the Ti64-M-ASP/PLGA substrate, with increased wettability and sustained release pattern of ASP. Compared with the Ti64 base material, the Ti64-M-ASP/PLGA substrate showed enhanced M2 and depressed M1 genes and proteins expressions in macrophages. The novel Ti64-M-ASP/PLGA substrate also displayed enhanced osteoblast proliferation, adhesion, extracellular mineralization ability and osteogenic gene expressions when cultured with macrophage conditioned medium in vitro. Furthermore, rat femora implantation model was used for in vivo evaluation. After 4 weeks of implantation, push out test, micro-computed tomography (micro-CT) and histological analyses all confirmed the superior osseointegration capabilities of the Ti64-M-ASP/PLGA implant than the other groups. Our study revealed the synergistic role played by 3D-printed micro topography and immunoregulatory drug aspirin in promoting osteogenesis in vitro and accelerating osseointegration in vivo, thus providing a promising method for better modifying the implant surface. Graphical abstract.

Pharmacological activities and mechanisms of action of Pogostemon cablin Benth: a review

Patchouli ("Guanghuoxiang") or scientifically known as Pogostemon cablin Benth, belonging to the family Lamiaceae, has been used in traditional Chinse medicine (TCM) since the time of the Eastern Han dynasty. In TCM theory, patchouli can treat colds, nausea, fever, headache, and diarrhea. Various bioactive compounds have been identified in patchouli, including terpenoids, phytosterols, flavonoids, organic acids, lignins, glycosides, alcohols, pyrone, and aldehydes. Among the numerous compounds, patchouli alcohol, β-patchoulene, patchoulene epoxide, pogostone, and pachypodol are of great importance. The pharmacological impacts of these compounds include anti-peptic ulcer effect, antimicrobial effect, anti-oxidative effect, anti-inflammatory effect, effect on ischemia/reperfusion injury, analgesic effect, antitumor effect, antidiabetic effect, anti-hypertensive effect, immunoregulatory effect, and others.For this review, we examined publications from the previous five years collected from PubMed, Web of Science, Springer, and the Chinese National Knowledge Infrastructure databases. This review summarizes the recent progress in phytochemistry, pharmacology, and mechanisms of action and provides a reference for future studies focused on clinical applications of this important plant extract.

Aspirin (single dose) for perineal pain in the early postpartum period

BACKGROUND

Perineal trauma, due to spontaneous tears, surgical incision (episiotomy), or in association with operative vaginal birth, is common after vaginal birth, and is often associated with postpartum perineal pain. Birth over an intact perineum may also lead to perineal pain. There are adverse health consequences associated with perineal pain for the women and their babies in the short- and long-term, and the pain may interfere with newborn care and the establishment of breastfeeding. Aspirin has been used in the management of postpartum perineal pain, and its effectiveness and safety should be assessed. This is an update of the review, last published in 2017.

OBJECTIVES

To determine the effects of a single dose of aspirin (acetylsalicylic acid), including at different doses, in the relief of acute postpartum perineal pain.

SEARCH METHODS

For this update, we searched the Cochrane Pregnancy and Childbirth's Trials Register (4 October 2019), ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (ICTRP) (4 October 2019) and screened reference lists of retrieved studies.

SELECTION CRITERIA

Randomised controlled trials (RCTs), assessing single dose aspirin compared with placebo, no treatment, a different dose of aspirin, or single dose paracetamol or acetaminophen, for women with perineal pain in the early postpartum period. We planned to include cluster-RCTs, but none were identified. We excluded quasi-RCTs and cross-over studies.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed study eligibility, extracted data and assessed the risk of bias of the included RCTs. Data were checked for accuracy. The certainty of the evidence for the main comparison (aspirin versus placebo) was assessed using the GRADE approach.

MAIN RESULTS

We included 17 RCTs, 16 of which randomised 1132 women to aspirin or placebo; one RCT did not report numbers of women. Two RCTs (of 16) did not contribute data to meta-analyses. All women had perineal pain post-episiotomy, and were not breastfeeding. Studies were published between 1967 and 1997, and the risk of bias was often unclear, due to poor reporting. We included four comparisons: aspirin versus placebo (15 RCTs); 300 mg versus 600 mg aspirin (1 RCT); 600 mg versus 1200 mg aspirin (2 RCTs); and 300 mg versus 1200 mg aspirin (1 RCT). Aspirin versus placebo Aspirin may result in more women reporting adequate pain relief four to eight hours after administration compared with placebo (risk ratio (RR) 2.03, 95% confidence interval (CI) 1.69 to 2.42; 13 RCTs, 1001 women; low-certainty evidence). It is uncertain whether aspirin compared with placebo has an effect on the need for additional pain relief (RR 0.25, 95% CI 0.17 to 0.37; 10 RCTs, 744 women; very low-certainty evidence), or maternal adverse effects (RR 1.08, 95% CI 0.57 to 2.06; 14 RCTs, 1067 women; very low-certainty evidence), four to eight hours after administration. Analyses based on dose did not reveal any clear subgroup differences. 300 mg versus 600 mg aspirin It is uncertain whether over four hours after administration, 300 mg compared with 600 mg aspirin has an effect on adequate pain relief (RR 0.82, 95% CI 0.36 to 1.86; 1 RCT, 81 women) or the need for additional pain relief (RR 0.68, 95% CI 0.12 to 3.88; 1 RCT, 81 women). There were no maternal adverse effects in either aspirin group. 600 mg versus 1200 mg aspirin It is uncertain whether over four to eight hours after administration, 600 mg compared with 1200 mg aspirin has an effect on adequate pain relief (RR 0.85, 95% CI 0.52 to 1.39; 2 RCTs, 121 women), the need for additional pain relief (RR 1.32, 95% CI 0.30 to 5.68; 2 RCTs, 121 women), or maternal adverse effects (RR 3.00, 95% CI 0.13 to 69.52; 2 RCTs, 121 women). 300 mg versus 1200 mg aspirin It is uncertain whether over four hours after administration, 300 mg compared with 1200 mg aspirin has an effect on adequate pain relief (RR 0.62, 95% CI 0.29 to 1.32; 1 RCT, 80 women) or need for additional pain relief (RR 2.00, 95% CI 0.19 to 21.18; 1 RCT, 80 women). There were no maternal adverse effects in either aspirin group. None of the included RCTs reported on neonatal adverse effects. No RCTs reported on secondary review outcomes of: prolonged hospitalisation due to perineal pain; re-hospitalisation due to perineal pain; fully breastfeeding at discharge; mixed feeding at discharge; fully breastfeeding at six weeks; mixed feeding at six weeks; perineal pain at six weeks; maternal views; or maternal postpartum depression.

AUTHORS' CONCLUSIONS

Single dose aspirin may increase adequate pain relief in women with perineal pain post-episiotomy compared with placebo. It is uncertain whether aspirin has an effect on the need for additional analgesia, or on maternal adverse effects, compared with placebo. We downgraded the certainty of the evidence because of study limitations (risk of bias), imprecision, and publication bias. Aspirin may be considered for use in non-breastfeeding women with post-episiotomy perineal pain. Included RCTs excluded breastfeeding women, so there was no evidence to assess the effects of aspirin on neonatal adverse effects or breastfeeding. Future RCTs should be designed to ensure low risk of bias, and address gaps in the evidence, such as the secondary outcomes established for this review. Current research has focused on women with post-episiotomy pain; future RCTs could be extended to include women with perineal pain associated with spontaneous tears or operative birth.

Icariin/Aspirin Composite Coating on TiO2 Nanotubes Surface Induce Immunomodulatory Effect of Macrophage and Improve Osteoblast Activity

Surface coating modification of titanium-based alloys is an efficient way to accelerate early osseointegration in dental implant fields. Icariin (ICA) is a traditional Chinese medicine that has bone activating functions, while aspirin (ASP) is a classical non-steroidal anti-inflammatory drug with good antipyretic and analgesic capabilities. Moreover, poly(lactic–co–glycolic acid) (PLGA) has attracted great attention due to its excellent biocompatibility and biodegradability. We superimposed an ASP/PLGA coating onto ICA loaded TiO2 nanotubes structure so as to establish an icariin/aspirin composite coating on TiO2 nanotubes surface. Scanning electron microscopy, X-ray photoelectron spectroscopy, a contact angle test and a drug release test confirmed the successful preparation of the NT–ICA–ASP/PLGA substrate, with a sustained release pattern of both ICA and ASP. Compared to those cultured on the Ti surface, macrophage cells on the NT-ICA-ASP/PLGA substrate displayed decreased M1 proinflammatory and enhanced M2 proregenerative genes and proteins expression, which implied activated immunomodulatory effect. Moreover, when cultured with conditioned medium from macrophages, osteoblast cells on the NT-ICA-ASP/PLGA substrate revealed improved cell proliferation, adhesion and osteogenic genes and proteins expression, compared with those on the Ti surface. The abovementioned results suggest that the established NT-ICA-ASP/PLGA substrate is a promising candidate for functionalized coating material in Ti implant surface modification.

A systematic review of cannabidiol dosing in clinical populations

AIMS

Cannabidiol (CBD) is a cannabis-derived medicinal product with potential application in a wide-variety of contexts; however, its effective dose in different disease states remains unclear. This review aimed to investigate what doses have been applied in clinical populations, in order to understand the active range of CBD in a variety of medical contexts.

METHODS

Publications involving administration of CBD alone were collected by searching PubMed, EMBASE and ClinicalTrials.gov.

RESULTS

A total of 1038 articles were retrieved, of which 35 studies met inclusion criteria covering 13 medical contexts. Twenty-three studies reported a significant improvement in primary outcomes (e.g. psychotic symptoms, anxiety, seizures), with doses ranging between <1 and 50 mg/kg/d. Plasma concentrations were not provided in any publication. CBD was reported as well tolerated and epilepsy was the most frequently studied medical condition, with all 11 studies demonstrating positive effects of CBD on reducing seizure frequency or severity (average 15 mg/kg/d within randomised controlled trials). There was no signal of positive activity of CBD in small randomised controlled trials (range n = 6-62) assessing diabetes, Crohn's disease, ocular hypertension, fatty liver disease or chronic pain. However, low doses (average 2.4 mg/kg/d) were used in these studies.

CONCLUSION

This review highlights that CBD has a potential wide range of activity in several pathologies. Pharmacokinetic studies as well as conclusive phase III trials to elucidate effective plasma concentrations within medical contexts are severely lacking and highly encouraged.

Effects of peri-operative nonsteroidal anti-inflammatory drugs on post-operative kidney function for adults with normal kidney function

BACKGROUND

Nonsteroidal anti-inflammatory drugs (NSAIDs) provide effective analgesia during the post-operative period but can cause acute kidney injury (AKI) when used peri-operatively (at or around the time of surgery). This is an update of a Cochrane review published in 2007.

OBJECTIVES

This review looked at the effect of NSAIDs used in the peri-operative period on post-operative kidney function in patients with normal kidney function.

SEARCH METHODS

We searched Cochrane Kidney and Transplant's Specialised Register to 4 January 2018 through contact with the Information Specialist using search terms relevant to this review. Studies in the Specialised Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

All randomised controlled trials (RCTs) and quasi-RCTs (RCTs in which allocation to treatment was obtained by alternation, use of alternate medical records, date of birth or other predictable methods) looking at the use of NSAIDs versus placebo for the treatment of post-operative pain in patients with normal kidney function were included.

DATA COLLECTION AND ANALYSIS

Data extraction was carried out independently by two authors as was assessment of risk of bias. Disagreements were resolved by a third author. Dichotomous outcomes are reported as relative risk (RR) and continuous outcomes as mean difference (MD) together with their 95% confidence intervals (CI). Meta-analyses were used to assess the outcomes of AKI, change in serum creatinine (SCr), urine output, renal replacement therapy (RRT), death (all causes) and length of hospital stay.

MAIN RESULTS

We identified 26 studies (8835 participants). Risk of bias was high in 17, unclear in 6and low in three studies. There was high risk of attrition bias in six studies.Only two studies measured AKI. The use of NSAIDs had uncertain effects on the incidence of AKI compared to placebo (7066 participants: RR 1.79, 95% CI 0.40 to 7.96; I2 = 59%; very low certainty evidence). One study was stopped early by the data monitoring committee due to increased rates of AKI in the NSAID group. Moreover, both of these studies were examining NSAIDs for indications other than analgesia and therefore utilised relatively low doses.Compared to placebo, NSAIDs may slightly increase serum SCr (15 studies, 794 participants: MD 3.23 μmol/L, 95% CI -0.80 to 7.26; I2 = 63%; low certainty evidence). Studies displayed moderate to high heterogeneity and had multiple exclusion criteria including age and so were not representative of patients undergoing surgery. Three of these studies excluded patients if their creatinine rose post-operatively.NSAIDs may make little or no difference to post-operative urine output compared to placebo (6 studies, 149 participants: SMD -0.02, 95% CI -0.31 to 0.27). No reliable conclusions could be drawn from these studies due to the differing units of measurements and measurement time points.It is uncertain whether NSAIDs leads to the need for RRT because the certainty of this evidence is very low (2 studies, 7056 participants: RR 1.57, 95% CI 0.49 to 5.07; I2 = 26%); there were few events and the results were inconsistent.It is uncertain whether NSAIDs lead to more deaths (2 studies, 312 participants: RR 1.44, 95% CI 0.19 to 11.12; I2 = 38%) or increased the length of hospital stay (3 studies, 410 participants: MD 0.12 days, 95% CI -0.48 to 0.72; I2 = 24%).

AUTHORS' CONCLUSIONS

Overall NSAIDs had uncertain effects on the risk of post-operative AKI, may slightly increase post-operative SCr, and it is uncertain whether NSAIDs lead to the need for RRT, death or increases the length of hospital stay. The available data therefore does not confirm the safety of NSAIDs in patients undergoing surgery. Further larger studies using the Kidney Disease Improving Global Outcomes definition for AKI including patients with co-morbidities are required to confirm these findings. .

Diclofenac Potassium in Acute Postoperative Pain and Dysmenorrhoea: Results from Comprehensive Clinical Trial Reports

We compared the efficacy of diclofenac potassium in unpublished clinical study reports (CSRs) and published reports to examine publication bias, industry bias, and comprehensiveness. Novartis provided CSRs of randomised double-blind trials of diclofenac potassium involving postoperative patients following third molar extraction (3 trials, n=519), gynaecological surgery (3 trials, n=679), and dysmenorrhoea (2 trials, n=711) conducted in 1988–1990. Searches identified published reports of 6 trials. Information from 599/1909 patients was not published; trials with 846/1909 patients were published in a defunct journal. Greater methodological information in CSRs contributed to lesser risk of bias than published trials. Numbers needed to treat (NNT) from CSRs for all six postoperative trials for at least 50% of maximum pain relief over 6 h were 2.2 (95% confidence interval, 1.9–2.6) and 2.1 (1.8–2.4) for 50 and 100 mg diclofenac potassium, respectively. A Cochrane review of published trial data reported NNTs of 2.1 and 1.9, and one comprehensive analysis reported NNTs of 2.2 and 2.1, respectively. All analyses had similar results for patients remedicating within 8 h. No data from dysmenorrhoea CSRs appeared in a Cochrane review. CSRs provide useful information and increase confidence. Stable efficacy estimates with standard study designs reduce the need for updating reviews.

Anti-nociceptive effect of patchouli alcohol: Involving attenuation of cyclooxygenase 2 and modulation of mu-opioid receptor

OBJECTIVE

To explore the anti-nociceptive effect of patchouli alcohol (PA), the essential oil isolated from Pogostemon cablin (Blanco) Bent, and determine the mechanism in molecular levels.

METHODS

The acetic acid-induced writhing test and formalin-induced plantar injection test in mice were employed to confirm the effect in vivo. Intracellular calcium ion was imaged to verify PA on mu-opioid receptor (MOR). Cyclooxygenase 2 (COX2) and MOR of mouse brain were expressed for determination of PA's target. Cellular experiments were carried out to find out COX2 and MOR expression induced by PA.

RESULTS

PA significantly reduced latency period of visceral pain and writhing induced by acetic acid saline solution (P<0.01) and allodynia after intra-plantar formalin (P<0.01) in mice. PA also up-regulated COX2 mRNA and protein (P<0.05) with a down-regulation of MOR (P<0.05) both in in vivo and in vitro experiments, which devote to the analgesic effect of PA. A decrease in the intracellular calcium level (P<0.05) induced by PA may play an important role in its anti-nociceptive effect. PA showed the characters of enhancing the MOR expression and reducing the intracellular calcium ion similar to opioid effect.

CONCLUSIONS

Both COX2 and MOR are involved in the mechanism of PA's anti-nociceptive effect, and the up-regulation of the receptor expression and the inhibition of intracellular calcium are a new perspective to PA's effect on MOR.

Aspirin (single dose) for perineal pain in the early postpartum period

BACKGROUND

Perineal trauma (due to spontaneous tears, surgical incision (episiotomy) or in association with operative vaginal birth) is common after vaginal birth, and is often associated with postpartum perineal pain. Birth over an intact perineum may also lead to perineal pain. There are adverse health consequences associated with perineal pain for the women and their babies in the short- and long-term, and the pain may interfere with newborn care and the establishment of breastfeeding. Aspirin has been used in the management of postpartum perineal pain and its effectiveness and safety should be assessed.

OBJECTIVES

To determine the efficacy of a single dose of aspirin (acetylsalicylic acid), including at different doses, in the relief of acute postpartum perineal pain.

SEARCH METHODS

We searched Cochrane Pregnancy and Childbirth's Trials Register (30 August 2016), ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (ICTRP) (31 May 2016) and reference lists of retrieved studies.

SELECTION CRITERIA

Randomised controlled trials (RCTs) assessing single dose aspirin compared with placebo, no treatment, a different dose of aspirin, or single dose paracetamol/acetaminophen for women with perineal pain in the early postpartum period. We planned to include cluster-RCTs but none were identified. Quasi-RCTs and cross-over studies were not eligible for inclusion in this review.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed study eligibility, extracted data and assessed the risk of bias of the included RCTs. Data were checked for accuracy. The quality of the evidence for the main comparison (aspirin versus placebo) was assessed using the GRADE approach.

MAIN RESULTS

We included 17 RCTs, with 16 involving 1132 women randomised to aspirin or placebo (one RCT did not report numbers of women). Two RCTs (of 16) did not contribute data to review meta-analyses. All women had perineal pain post-episiotomy, and were not breastfeeding. Studies were published between 1967 and 1997, and the risk of bias was often unclear due to poor reporting.We included four comparisons: aspirin versus placebo (data from 15 RCTs); 300 mg versus 600 mg aspirin (1 RCT); 600 mg versus 1200 mg aspirin (2 RCTs); and 300 mg versus 1200 mg aspirin (1 RCT). Primary outcomes Aspirin versus placeboMore women who received aspirin experienced adequate pain relief compared with women who received placebo over four to eight hours after administration (risk ratio (RR) 2.03, 95% confidence intervals (CI) 1.69 to 2.42; 13 RCTs, 1001 women; low-quality evidence). Women who received aspirin were less likely to need additional pain relief over four to eight hours after administration (RR 0.25, 95% CI 0.17 to 0.37; 10 RCTs, 744 women; very low-quality evidence). There was no difference in maternal adverse effects over four to eight hours post-administration (RR 1.08, 95% CI 0.57 to 2.06; 14 RCTs, 1067 women; very low-quality evidence). Subgroup analyses based on dose did not reveal any clear subgroup differences.There was no clear difference over four hours after administration between 300 mg and 600 mg aspirin for adequate pain relief (RR 0.82, 95% CI 0.36 to 1.86; 1 RCT, 81 women) or need for additional pain relief (RR 0.68, 95% CI 0.12 to 3.88; 1 RCT, 81 women). There were no maternal adverse effects in either aspirin group.There was no clear difference over four to eight hours after administration between 600 mg and 1200 mg aspirin for adequate pain relief (RR 0.85, 95% CI 0.52 to 1.39; 2 RCTs, 121 women), need for additional pain relief (RR 1.32, 95% CI 0.30 to 5.68; 2 RCTs, 121 women), or maternal adverse effects (RR 3.00, 95% CI 0.13 to 69.52; 2 RCTs, 121 women).There was no clear difference over four hours after administration between 300 mg and 1200 mg aspirin for adequate pain relief (RR 0.62, 95% CI 0.29 to 1.32; 1 RCT, 80 women) or need for additional pain relief (RR 2.00, 95% CI 0.19 to 21.18; 1 RCT, 80 women). There were no maternal adverse effects in either aspirin group.None of the included RCTs reported on neonatal adverse effects. Secondary outcomesNo studies reported on secondary review outcomes: prolonged hospitalisation due to perineal pain; re-hospitalisation due to perineal pain; fully breastfeeding at discharge; mixed feeding at discharge; fully breastfeeding at six weeks; mixed feeding at six weeks; perineal pain at six weeks; maternal views; maternal postpartum depression.

AUTHORS' CONCLUSIONS

We found low-quality evidence to suggest that single dose aspirin compared with placebo can increase pain relief in women with perineal pain post-episiotomy. Very low-quality evidence also suggested that aspirin can reduce the need for additional analgesia, without increasing maternal adverse effects. Evidence was downgraded based on study limitations (risk of bias), imprecision, and publication bias or both. RCTs excluded breastfeeding women so there is no evidence to assess the effects of aspirin on neonatal adverse effects or breastfeeding.With international guidance recommending mothers initiate breastfeeding within one hour of birth, and exclusively breastfeed for the first six months, the evidence from this review is not applicable to current recommended best practice. Aspirin may be considered for use in non-breastfeeding women with post-episiotomy perineal pain. Although formal assessment was beyond the remit of this review, current guidance suggests that other analgesic drugs (including paracetamol) should be considered first for postpartum perineal pain. Such agents are the focus of other reviews in this series on drugs for perineal pain in the early postpartum period. It is considered most likely that if RCTs are conducted in the future they could compare aspirin with other pain relievers. Future RCTs should be designed to ensure high methodological quality, and address gaps in the evidence, such as the secondary outcomes established for this review. Current research has focused on women with post-episiotomy pain, future RCTs could be extended to women with perineal pain associated with spontaneous tears or operative birth.

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 celecoxib for acute postoperative pain in adults

BACKGROUND

This is an update of a review first published in The Cochrane Library in Issue 4, 2008, and updated in Issue 3, 2012. Celecoxib is a selective cyclo-oxygenase-2 (COX-2) inhibitor usually prescribed for the relief of chronic pain in osteoarthritis and rheumatoid arthritis. Celecoxib is believed to be associated with fewer upper gastrointestinal adverse effects than conventional non-steroidal anti-inflammatory drugs (NSAIDs). Its effectiveness in acute pain was demonstrated in the earlier reviews.

OBJECTIVES

To assess analgesic efficacy and adverse effects of a single oral dose of celecoxib for moderate to severe postoperative pain in adults.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, the Oxford Pain Database, and ClinicalTrials.gov. The most recent search was to 31 May 2013.

SELECTION CRITERIA

We included randomised, double-blind, placebo-controlled trials (RCTs) of adults prescribed any dose of oral celecoxib or placebo for acute postoperative pain.

DATA COLLECTION AND ANALYSIS

Two review authors assessed studies for quality and extracted data. We converted summed pain relief (TOTPAR) or pain intensity difference (SPID) into dichotomous information, yielding the number of participants with at least 50% pain relief over four to six hours. We used this to calculate the relative benefit (RB) and number needed to treat to benefit (NNT), for one patient to achieve at least 50% of maximum pain relief with celecoxib who would not have done so with 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.

MAIN RESULTS

Ten studies (1785 participants) met the inclusion criteria. The two new studies in this update had been identified in the earlier update, but data were not available. There remain three potentially relevant unpublished studies for which data are not available at this time.The NNT for celecoxib 200 mg and 400 mg compared with placebo for at least 50% of maximum pain relief over four to six hours was 4.2 (95% confidence interval (CI) 3.4 to 5.6) and 2.6 (95% CI 2.3 to 3.0) respectively. The median time to use of rescue medication was 6.6 hours with celecoxib 200 mg, 8.4 hours with celecoxib 400 mg, and 2.3 hours with placebo. The proportion of participants requiring rescue medication over 24 hours was 74% with celecoxib 200 mg, 63% for celecoxib 400 mg, and 91% for placebo. The NNT to prevent one patient using rescue medication was 4.8 (95% CI 3.5 to 7.7) and 3.5 (95% CI 2.9 to 4.6) for celecoxib 200 mg and 400 mg respectively. Adverse events were generally mild to moderate in severity, and were experienced by a similar proportion of participants in the celecoxib and placebo groups. One serious adverse event that was probably related to celecoxib was reported.

AUTHORS' CONCLUSIONS

Single-dose oral celecoxib is an effective analgesic for postoperative pain relief. Indirect comparison suggests that the 400 mg dose has similar efficacy to ibuprofen 400 mg.

Single dose oral celecoxib for acute postoperative pain in adults

BACKGROUND

This is an update of a review published in The Cochrane Library 2008, Issue 4. Celecoxib is a selective cyclo-oxygenase-2 (COX-2) inhibitor usually prescribed for the relief of chronic pain in osteoarthritis and rheumatoid arthritis. Celecoxib is believed to be associated with fewer upper gastrointestinal adverse effects than conventional non-steroidal anti-inflammatory drugs (NSAIDs). Its effectiveness in acute pain was demonstrated in the earlier reviews.

OBJECTIVES

To assess analgesic efficacy and adverse effects of a single oral dose of celecoxib for moderate to severe postoperative pain.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, the Oxford Pain Database, and ClinicalTrials.gov. The most recent search was to 3 January 2012.

SELECTION CRITERIA

We included randomised, double-blind, placebo-controlled trials (RCTs) of adults prescribed any dose of oral celecoxib or placebo for acute postoperative pain.

DATA COLLECTION AND ANALYSIS

Two review authors assessed studies for quality and extracted data. We converted summed pain relief (TOTPAR) or pain intensity difference (SPID) into dichotomous information, yielding the number of participants with at least 50% pain relief over four to six hours, and used this to calculate the relative benefit (RB) and number needed to treat to benefit (NNT) for one patient to achieve at least 50% of maximum pain relief with celecoxib who would not have done so with 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.

MAIN RESULTS

Eight studies (1380 participants) met the inclusion criteria. We identified five potentially relevant unpublished studies in the most recent searches, but data were not available at this time. The number of included studies therefore remains unchanged.The NNT for celecoxib 200 mg and 400 mg compared with placebo for at least 50% of maximum pain relief over four to six hours was 4.2 (95% confidence interval (CI) 3.4 to 5.6) and 2.5 (2.2 to 2.9) respectively. The median time to use of rescue medication was 6.6 hours with celecoxib 200 mg, 8.4 with celecoxib 400 mg, and 2.3 hours with placebo. The proportion of participants requiring rescue medication over 24 hours was 74% with celecoxib 200 mg, 63% for celecoxib 400 mg, and 91% for placebo. The NNT to prevent one patient using rescue medication was 4.8 (3.5 to 7.7) and 3.5 (2.9 to 4.6) for celecoxib 200 mg and 400 mg respectively. Adverse events were generally mild to moderate in severity, and were experienced by a similar proportion of participants in celecoxib and placebo groups. One serious adverse event probably related to celecoxib was reported.

AUTHORS' CONCLUSIONS

Single-dose oral celecoxib is an effective analgesic for postoperative pain relief. Indirect comparison suggests that the 400 mg dose has similar efficacy to ibuprofen 400 mg.