Single dose oral paracetamol (acetaminophen) for postoperative pain in adults
Editorial Group: Cochrane Pain, Palliative and Supportive Care Group
Published Online: 8 OCT 2008
Assessed as up-to-date: 31 JUL 2008
Copyright © 2012 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.
How to Cite
Toms L, McQuay HJ, Derry S, Moore RA. Single dose oral paracetamol (acetaminophen) for postoperative pain in adults. Cochrane Database of Systematic Reviews 2008, Issue 4. Art. No.: CD004602. DOI: 10.1002/14651858.CD004602.pub2.
- Publication Status: Stable (no update expected for reasons given in 'What's new')
- Published Online: 8 OCT 2008
This is an updated version of the original Cochrane review published in Issue 1, 2004 - this original review had been split from a previous title on 'Single dose paracetamol (acetaminophen) with and without codeine for postoperative pain'. The last version of this review concluded that paracetamol is an effective analgesic for postoperative pain, but additional trials have since been published. This review sought to evaluate the efficacy and safety of paracetamol using current data, and to compare the findings with other analgesics evaluated in the same way.
To assess the efficacy of single dose oral paracetamol for the treatment of acute postoperative pain.
We searched The Cochrane Library, MEDLINE, EMBASE, the Oxford Pain Relief Database and reference lists of articles to update an existing version of the review in July 2008.
Randomised, double-blind, placebo-controlled clinical trials of paracetamol for acute postoperative pain in adults.
Data collection and analysis
Two review authors independently assessed trial quality and extracted data. Area under the “pain relief versus time” curve was used to derive the proportion of participants with paracetamol or placebo experiencing at least 50% pain relief over four to six hours, using validated equations. Number-needed-to-treat-to-benefit (NNT) was calculated, with 95% confidence intervals (CI). The proportion of participants using rescue analgesia over a specified time period, and time to use, were sought as measures of duration of analgesia. Information on adverse events and withdrawals was also collected.
Fifty-one studies, with 5762 participants, were included: 3277 participants were treated with a single oral dose of paracetamol and 2425 with placebo. About half of participants treated with paracetamol at standard doses achieved at least 50% pain relief over four to six hours, compared with about 20% treated with placebo. NNTs for at least 50% pain relief over four to six hours following a single dose of paracetamol were as follows: 500 mg NNT 3.5 (2.7 to 4.8); 600 to 650 mg NNT 4.6 (3.9 to 5.5); 975 to 1000 mg NNT 3.6 (3.4 to 4.0). There was no dose response. Sensitivity analysis showed no significant effect of trial size or quality on this outcome.
About half of participants needed additional analgesia over four to six hours, compared with about 70% with placebo. Five people would need to be treated with 1000 mg paracetamol, the most commonly used dose, to prevent one needing rescue medication over four to six hours, who would have needed it with placebo. Adverse event reporting was inconsistent and often incomplete. Reported adverse events were mainly mild and transient, and occurred at similar rates with 1000 mg paracetamol and placebo. No serious adverse events were reported. Withdrawals due to adverse events were uncommon and occurred in both paracetamol and placebo treatment arms.
A single dose of paracetamol provides effective analgesia for about half of patients with acute postoperative pain, for a period of about four hours, and is associated with few, mainly mild, adverse events.
Plain language summary
Single dose oral paracetamol (acetaminophen) for postoperative pain relief in adults
Pain is commonly experienced after surgical procedures, and is not always well controlled. This review assessed data from fifty-one studies and found that paracetamol provided effective pain relief for about half of participants experiencing moderate to severe pain after an operation, including dental surgery for a period of about four hours. There were no clear differences between doses of paracetamol typically used. These single dose studies did not associate paracetamol with any serious side effects.
單一劑量口服paracetamol (acetaminophen) 作為手術後止痛
Paracetamol (acetaminophen) 和非類固醇類抗發炎藥物(NSAIDs) 廣泛被應用在輕度和中度疼痛,從頭痛、肌肉骨骼系統到經痛等。之前的Cochrane 系統性回顧認為, paracetamol 對手術後止痛有效的, 而且其他的試驗也已經有類似的發表了。這次回顧尋求評估paracetamol 在現今資料的效果和安全性, 並以相同研究方式來評估其與其它止痛藥的比較。
評估單一劑量口服paracetamol (acetaminophen) 作為手術後急性止痛的效果。
為了更新一個已有的回顧版本,我們找出Cochrane Library (Issue 3, 2002), the trials register of the Cochrane Pain, Palliative and Supportive Care group (November 2002); MEDLINE (1966 to May 1996); PubMed (1996 to August2001); EMBASE (1980 to 1996); the Oxford Pain Relief Database (1950 to 1994); 及文章中列出之參考文獻。
隨機化的, 雙盲, 以安慰劑為控制組的paracetamol 在成人臨床試驗上對手術後止痛的影響.
二位回顧者分別地評估試驗的質和擷取了資料。在疼痛緩解對時間曲線下區域表示患者使用paracetamol 或安慰劑因而在四個到六個小時獲得最少50%疼痛緩解。需要被治療的數目(NNT) 估計使用95% 信賴區間隔。同時也收集了關於副作用的訊息。
四十七個研究報告, 包含4186 名患者(2561 名患者給予以單一口服藥量paracetamol 和1625 名患者給予安慰劑) 符合了納入標準因而包括在分析中。給予paracetamol 單一劑量產生至少50%疼痛緩解四到六個小時而NNTs如下 : 325 毫克NNT 3.8 (2.2 到13.3); 500 毫克NNT 3.5 (2.7 到4.8); 600/650 毫克NNT 4.6 (3.9 到5.5); 975/1000 毫克NNT 3.8 (3.4 到4.4); 並且1500 毫克NNT 3.7 (2.3 到9.5) 。子群分析顯示在較小和較大的試驗之間或較低和較高的試驗品質沒有明顯的差別。與藥物相關的戒斷研究很少被報導。研究報告副作用的發生率一般是很少且短暫的。在paracetamol 975/1000 毫克和在安慰劑之間的副作用發生率在統計上是沒有明顯的差異。
此翻譯計畫由臺灣國家衛生研究院(National Health Research Institutes, Taiwan)統籌。
Paracetamol 在成人術後中度到強烈疼痛是有效的.疼痛在外科手術後是常見的, 但總是沒有好好控制。這次回顧評估計包含四十七個試驗而發現paracetamol 對中度到強烈術後疼痛是有效的, 包括了牙科手術。在paracetamol 藥量劑量之間是沒有很大的差別。在回顧中的試驗沒有任何一起嚴重的副作用是跟paracetamol 有關的。