Intervention Review

Acetaminophen for osteoarthritis

  1. Tanveer Towheed1,*,
  2. Lara Maxwell2,
  3. Maria Judd3,
  4. Michelle Catton4,
  5. Marc C Hochberg5,
  6. George A Wells6

Editorial Group: Cochrane Musculoskeletal Group

Published Online: 25 JAN 2006

Assessed as up-to-date: 31 OCT 2005

DOI: 10.1002/14651858.CD004257.pub2

How to Cite

Towheed T, Maxwell L, Judd M, Catton M, Hochberg MC, Wells GA. Acetaminophen for osteoarthritis. Cochrane Database of Systematic Reviews 2006, Issue 1. Art. No.: CD004257. DOI: 10.1002/14651858.CD004257.pub2.

Author Information

  1. 1

    Queen's University, Department of Medicine and of Community Health and Epidemiology, Kingston, Ontario, Canada

  2. 2

    University of Ottawa, Institute of Population Health, Ottawa, Ontario, Canada

  3. 3

    Canadian Health Services Research Foundation/Fondation canadienne de la recherche sur les services de santé, Research Use/Agente principale de programme, Utilisation de la Recherche, Ottawa, Ontario, Canada

  4. 4

    Ottawa, Ontario, Canada

  5. 5

    University of Maryland, School of Medicine, Baltimore, MD, USA

  6. 6

    University of Ottawa Heart Institute, Cardiovascular Research Reference Centre, Ottawa, Ontario, Canada

*Tanveer Towheed, Department of Medicine and of Community Health and Epidemiology, Queen's University, Etherington Hall-Room 2066, Kingston, Ontario, K7L 3N6, Canada.

Publication History

  1. Publication Status: Edited (no change to conclusions)
  2. Published Online: 25 JAN 2006




  1. Top of page
  2. Abstract
  3. Plain language summary
  4. 摘要


Osteoarthritis (OA) is the most common form of arthritis. Published guidelines and expert opinion are divided over the relative role of acetaminophen (also called paracetamol or Tylenol) and non-steroidal anti-inflammatory drugs (NSAIDs) as first-line pharmacologic therapy. The comparative safety of acetaminophen and NSAIDs is also important to consider. This update to the original 2003 review includes nine additional RCTs.


To assess the efficacy and safety of acetaminophen versus placebo and versus NSAIDs (ibuprofen, diclofenac, arthrotec, celecoxib, naproxen, rofecoxib) for treating OA.

Search methods

We searched MEDLINE (up to July 2005), EMBASE (2002-July 2005), Cochrane Central Register of Controlled Trials (CENTRAL), ACP Journal Club, DARE, Cochrane Database of Systematic Reviews (all from 1994 to July 2005). Reference lists of identified RCTs and pertinent review articles were also hand searched.

Selection criteria

Published randomized controlled trials (RCTs) evaluating the efficacy and safety of acetaminophen alone in OA were considered for inclusion.

Data collection and analysis

Pain, physical function and global assessment outcomes were reported. Results for continuous outcome measures were expressed as standardized mean differences (SMD). Dichotomous outcome measures were pooled using relative risk (RR) and the number needed to treat (NNT) was calculated.

Main results

Fifteen RCTs involving 5986 participants were included in this review. Seven RCTs compared acetaminophen to placebo and ten RCTs compared acetaminophen to NSAIDs. In the placebo-controlled RCTs, acetaminophen was superior to placebo in five of the seven RCTs and had a similar safety profile. Compared to placebo, a pooled analysis of five trials of overall pain using multiple methods demonstrated a statistically significant reduction in pain (SMD -0.13, 95% CI -0.22 to -0.04), which is of questionable clinical significance. The relative percent improvement from baseline was 5% with an absolute change of 4 points on a 0 to 100 scale. The NNT to achieve an improvement in pain ranged from 4 to 16. In the comparator-controlled RCTs, acetaminophen was less effective overall than NSAIDs in terms of pain reduction, global assessments and in terms of improvements in functional status. No significant difference was found overall between the safety of acetaminophen and NSAIDs, although patients taking traditional NSAIDS were more likely to experience an adverse GI event (RR 1.47, (95% CI 1.08 to 2.00). 19% of patients in the traditional NSAID group versus 13% in the acetaminophen group experienced an adverse GI event. However, the median trial duration was only 6 weeks and it is difficult to assess adverse outcomes in a relatively short time period.

Authors' conclusions

The evidence to date suggests that NSAIDs are superior to acetaminophen for improving knee and hip pain in people with OA. The size of the treatment effect was modest, and the median trial duration was only six weeks, therefore, additional considerations need to be factored in when making the decision between using acetaminophen or NSAIDs. In OA subjects with moderate-to-severe levels of pain, NSAIDs appear to be more effective than acetaminophen.


Plain language summary

  1. Top of page
  2. Abstract
  3. Plain language summary
  4. 摘要

Acetaminophen for osteoarthritis

How well does acetaminophen work and compare to anti-inflammatories to treat osteoarthritis and is it safe?

Fifteen studies of moderate to high quality were reviewed and provide the best evidence we have today. The studies tested almost 6000 people with osteoarthritis of the hip or knee. The studies compared people who took 4000 mg of acetaminophen (Tylenol, Paracetamol) a day to people who took a placebo (fake pill) or non-steroidal anti-inflammatory drugs (NSAIDs). Most studies lasted on average about 6 weeks.

What is osteoarthritis and what drugs are used to treat it?
Osteoarthritis (OA) is the most common form of arthritis that can affect the hands, hips, shoulders and knees. In OA, the cartilage that protects the ends of the bones breaks down and causes pain and swelling. There are two main types of drug treatments in OA: acetaminophen which is used to relieve pain but does not affect swelling; and NSAIDs, such as ibuprofen, diclofenac and cox IIs (celecoxib), which are used to decrease pain and swelling. It is not clear which type is best to use or which causes more side effects: high doses of acetaminophen may cause stomach problems, such as ulcers, and NSAIDs may cause stomach, kidney or heart problems.

What did the studies show?
Acetaminophen compared to placebo
The studies show that people who took acetaminophen has less pain (when resting, moving, sleeping and overall) and felt better overall than people who took a placebo. Pain (when measured on a different scale), physical function and stiffness were about the same.
• Pain decreased by 4 more points on a scale of 0-100 for people who took acetaminophen instead of a placebo.



  1. Top of page
  2. Abstract
  3. Plain language summary
  4. 摘要



骨性關節炎是最常見的關節炎。 已發表準則及專家意見對將乙醯胺酚acetaminophen(又名paracetamol 或 Tylenol)及非類固醇抗炎藥(NSAIDs)作為是第一線藥物治療意見分歧。乙醯胺酚及非類固醇抗炎藥的安全性比較也是需要重視的。此文以9組額外隨機對照試驗更新了2003回顧評論。


評估骨性關節炎用乙醯胺酚相對於安慰劑及非類固醇抗炎藥(布洛芬(ibuprofen), 雙氯芬酸(diclofenac),arthrotec(Diclofenac Na + misoprostol), 希樂葆(celecoxib),奈普生(naproxen),偉克適錠(rofecoxib)療效和安全性。


我們搜尋醫學文獻(MEDLINE)至2005 7月 止),醫學文摘(EMBASE) (2002至2005 7月止),科克倫中央登記冊對照試驗(Cochrane Central Register of Controlled Trials (CENTRAL)),非加太國家雜誌俱樂部 (ACP Journal Club),摘要回顧評論資料庫(DARE),Cochrane系統評價資料庫(Cochrane Database of Systematic Reviews)(所有從1994 至20057月)。確定隨機對照試驗及有關回顧評論文章的參考名單也手動搜查。




對疼痛,身體功能及整體評估結果需報告。 連續結果評估所得之資料是以標準化平均差(SMD)表示。二分法評估結果以相對危險度(RR)匯整並計算需要治療數目(NNT)。


◆ 這次回顧評論包括15組隨機對照試驗內含5986參加者。7組隨機對照試驗組比較乙醯胺酚及安慰劑,10組隨機對照試驗比較乙醯胺酚及非類固醇抗炎藥。在安慰劑 −控制 隨機對照試驗7組隨機對照試驗中有5組,乙醯胺酚比安慰劑為優並且有類似的安全性。與安慰劑比較,5 組試驗使用多種方法匯總分析整體疼痛 表明疼痛統計上顯著減少(SMD −0.13, 95% CI −0.22 to −0.04),但是臨床意義仍有疑問。從基線改善相對百分比是5% 這是從0至100點看絕對變化有4點。疼痛需要治療數目改善從4至16不等。在比較藥物控制隨機對照試驗,就疼痛減少,整體評估及就功能狀態改善整體效果乙醯胺酚比非類固醇抗炎藥為差。整體上乙醯胺酚及非類固醇抗炎藥之安全性之間無顯著性差異,儘管患者服用傳統的非類固醇抗炎藥更可能經驗胃腸不適(RR 1.47, (95% CI 1.08 to 2.00)。經驗胃腸不適,傳統的非類固醇抗炎藥組19%與對乙?氨基酚組13%。但是,試用期中位數僅僅6週,在相對較短的期限內很難評估不良後果。





此翻譯計畫由臺灣國家衛生研究院(National Health Research Institutes, Taiwan)統籌。


治療骨性關節炎乙醯胺酚運作如何,與抗炎藥比較,它安全嗎?回顧評論15中到高品質研究,已提供我們當今最好的證據。研究測試幾乎6000膝或髖關節炎病人。研究比較病人一天服用 4000毫克乙醯胺酚(Tylenol, Paracetamol)病人一天服用安慰劑(假藥丸)或非類固醇抗炎藥(NSAIDs)。大多數研究平均持續了約6週。什麼是骨關節炎及用哪些藥物是來治療?骨性關節炎是最常見的關節炎,這可能會影響手,髖,肩膀和膝蓋。在骨性關節炎,保護骨頭兩端的軟骨破裂並導致疼痛和腫脹。主要有兩種類型的藥物治療骨性關節炎:乙醯胺酚是用來緩解疼痛,但並不影響腫脹非類固醇抗炎藥,如布洛芬,雙氯芬酸和COX2者(希樂葆),用來減少疼痛和腫脹。目前尚不清楚最好使用哪種類型,或哪種類型造成更多的副作用:高劑量的乙醯胺酚可導致胃部問題,如胃潰瘍,與非類固醇抗炎藥可能會導致胃,腎臟或心臟問題。研究顯示了什麼? 乙醯胺酚與安慰劑相比研究表明,病人服用了乙醯胺酚疼痛較少(休息時,運動,睡眠和整體)並總的感覺更好。疼痛(用不同的衡量尺度),身體機能和僵硬度都差不多.. 從0至100點看服用了乙醯胺酚疼痛減少了4點,而安慰劑不是。 乙醯胺酚與非類固醇抗炎藥相比 研究表明,非類固醇抗炎藥的人較少疼痛和僵硬,並比服用乙醯胺酚的人們有更佳的身體機能.. 服用非類固醇抗炎藥在由0100尺度下疼痛減少了6個百分點。乙醯胺酚和非類固醇抗炎藥多安全?在比較服用乙醯胺酚或服用安慰劑或病人服用乙醯胺酚或非類固醇抗炎藥,副作用的類型和數量大致相同。當比較COX2與非類固醇抗炎藥時這也是如此。然而,病人服用傳統的非類固醇抗炎藥,如布洛芬或奈普生, 比病人服用對乙醯胺酚更易有胃病 (腹瀉,噁心,胃灼熱或胃痛)。用傳統的非類固醇抗炎藥100人中19人有副作用。用乙醯胺酚100人中13人有副作用。這是底線了嗎?證據的質量水平是‘金標準’ 。在髖或膝骨性關節炎病人,乙醯胺酚改善疼痛超過無治療。 非類固醇抗炎藥改善疼痛,功能和僵硬度超過乙醯胺酚,尤其是在中度至重度疼痛病人。 在乙醯胺酚與非類固醇抗炎藥之間副作用似乎沒有主要的差異,儘管人們服用傳統的非類固醇抗炎藥較可能有胃的問題。 藥品之間的好壞差別為中等,而研究只有大約6個星期長。 因此,決定時要考慮偏好,風險,費用,藥物可提供性及醫生的判斷。