Acetaminophen (Tylenol): An “easy” fix for knee and hip osteoarthritis?

The Bottom Line

  • Osteoarthritis is one of the top causes of disability worldwide.  
  • Tylenol, also commonly known as acetaminophen or paracetamol, is often the first treatment option tried for knee and hip osteoarthritis. 
  • In people with knee or hip osteoarthritis, Tylenol provides marginal improvements in pain (immediately/short-term) and physical function (short-term), but not likely to a degree that makes a meaningful impact.
  • Overall, Tylenol does not increase the risk of negative side effects. 
  • Other potentially effective treatment options for osteoarthritis include: non‐steroidal anti‐inflammatory drugs (NSAIDs), exercise, acupuncture, and surgery.
  • Start a discussion with your health care provider about the risks and benefits of different treatment options for knee and hip osteoarthritis. 

Acetaminophen, paracetamol, Tylenol... The use of these terms interchangeably can leave us getting Shakespearean and asking, what’s in a name? In this case, the answer is nothing. These three names all refer to the same medication, the only difference being that Tylenol is a brand name, while acetaminophen and paracetamol are generic names.

Tylenol is a common fixture in many of our medicine cabinets. It’s one of our go-to methods for relief from fevers, and all sorts of aches and pains. One particular kind of pain that has us opening those cabinet doors is arthritis pain (1). Over 4.7 million Canadians aged 50 years and older live with arthritis (2). When it comes to the top contributors of disability worldwide (1;3), osteoarthritis—the most common type of arthritis (4;5)—makes the list (3). Because osteoarthritis pain hinders our ability to move and function well physically (1), managing it is an important goal for both patients and doctors.

Joints that carry our weight (4), such as the knees and hips, are locations that often bare the negative consequences of osteoarthritis (3;6). But just what is the first treatment option most often recommend for treating knee and hip osteoarthritis pain? You guessed it…Tylenol (1;7-8). Interestingly, as the evidence-base on the use of Tylenol grows, so does the debate around its use for treating knee and hip osteoarthritis. In particular, issues around how effective and safe this treatment option is are being raised (1;9-11).

What the research tells us

A recent systematic review comparing the use of paracetamol (a.k.a. acetaminophen or Tylenol) versus placebo for treating knee and hip osteoarthritis reported several interesting findings.

First and foremost, when it comes to pain, in both the immediate term (two weeks or less) and short-term (more than two weeks but three months or less), Tylenol only provides marginal improvements. Second, while Tylenol most likely does not enhance physical function immediately, it does provide small improvements in the short-term. With that said, in all instances where benefits were seen, the size of the difference was so small that the authors concluded that taking Tylenol daily likely would not make a meaningful impact on the lives of folks with knee and hip osteoarthritis in the immediate term or short-term.

What about the potential for negative side effects?

Overall, people with knee and hip osteoarthritis taking Tylenol do not appear to have a higher chance of experiencing negative side effects. Also worth mentioning, is that the risk of an abnormal liver function test—which relates to liver toxicity—may increase with Tylenol use. But this finding lacks certainty because of the reliability of the evidence. Remember, in terms of safety, always use medications as instructed by the package or a pharmacist, or as prescribed by a health care provider.

Taking into consideration both the findings on the limited benefits and the potential for harms, the authors of the review call for the use of Tylenol as the first-treatment option for people with knee or hip osteoarthritis to be reevaluated (1).

This might leave some wondering, if not Tylenol than what?

Doctors will often recommend over-the-counter non‐steroidal anti‐inflammatory drugs (NSAIDs)—such as celecoxib , diclofenac, ibuprofen, and naproxen—when Tylenol is not cutting it (1;12-14). Evidence shows that oral NSAIDs—specifically diclofenac, ibuprofen, and naproxen—are more effective in reducing pain than Tylenol in people with knee osteoarthritis. Oral NSAIDs can also be more effective than Tylenol in improving both physical functioning and reducing stiffness (14). Despite this, Tylenol is often used as a first-line treatment because it‘s seen as being a safer option (1). For instance, NSAIDs may come with an increased risk of heart attack and/gastrointestinal issues (14;15). More research comparing the safety of these treatment options is needed (14).

Non-drug options for dealing with knee or hip osteoarthritis—including exercise, acupuncture, and surgery—can also be effective. Click on the links below for more information on these strategies:

All in all, these results do not mean you should be eager to stop a treatment recommended by your health care provider or start a new one they have not recommended. Instead, open a discussion about the different drug and non-drug treatment options available and the pros and cons of each for you.

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Author Details


  1. Leopoldino AO, Machado GC, Ferreira PH, et al. Paracetamol versus placebo for knee and hip osteoarthritis. Cochrane Database Syst Rev. 2019; 2:CD013273. doi: 10.1002/14651858.CD013273. 
  2. Statistics Canada. Arthritis, by age group. [Internet] 2020. [cited January 2020]. Available from
  3. Vos T, Flaxman AD, Naghavi M, et al. Years lived with disability (YLDs) for 1160 sequelae of 289 diseases and injuries 1990–2010: A systematic analysis for the Global Burden of Disease Study 2010. Lancet. 2012; 380:2163‐2196. doi: 10.1016/S0140-6736(12)61729-2. 
  4. Towheed T, Maxwell L, Judd M, et al. Acetaminophen for osteoarthritis. Cochrane Database Syst Rev. 2006; 1:CD004257. doi: 10.1002/14651858.CD004257.pub2. 
  5. Bradley JD, Brandt KD, Katz BP, et al. Comparison of an antiinflammatory dose of ibuprofen, an analgesic dose of ibuprofen, and acetaminophen in the treatment of patients with osteoarthritis of the knee. N Engl J Med. 1991; 325(2):87-91. doi: 10.1056/NEJM199107113250203.  
  6. Regnaux JP, Lefevre-Colau MM, Trinquart L, et al. High-intensity versus low-intensity physical activity or exercise in people with hip or knee osteoarthritis. Cochrane Database Syst Rev. 2015; 10:CD010203. doi: 10.1002/14651858.CD010203.pub2.
  7. Hochberg MC, Altman RD, April KT, et al. American College of Rheumatology 2012 recommendations for the use of nonpharmacologic and pharmacologic therapies in osteoarthritis of the hand, hip, and knee. Arthritis Care Res. 2012; 64:465‐474. doi: 10.1002/acr.21596. 
  8. Zhang W, Doherty M, Arden N, et al. EULAR evidence based recommendations for the management of hip osteoarthritis: Report of a task force of the EULAR Standing Committee for International Clinical Studies Including Therapeutics (ESCISIT). Ann Rheum Dis. 2005; 64(5):669-681. doi: 10.1136/ard.2004.028886. 
  9. Zhang W, Jones A, Doherty M. Does paracetamol (acetaminophen) reduce the pain of osteoarthritis? A meta‐analysis of randomised controlled trials. Ann Rheum Dis. 2004; 63(8):901‐907. doi: 10.1136/ard.2003.018531. 
  10. Zhang WG, Nuki RW, Moskowitz S, et al. OARSI recommendations for the management of hip and knee osteoarthritis: Part III: Changes in evidence following systematic cumulative update of research published through January 2009. Osteoarthritis Cartilage. 2010; 18(4):476‐499. doi: 10.1016/j.joca.2010.01.013. 
  11. Roberts E, Delgado Nunes V, Buckner S, et al. Paracetamol: Not as safe as we thought? A systematic literature review of observational studies. Ann Rheum Dis. 2016; 75(3):552‐559. doi: 10.1136/annrheumdis-2014-206914.
  12. Derry S, Conaghan P, Silva JA, et al. Topical NSAIDs for chronic musculoskeletal pain in adults. Cochrane Database Syst Rev. 2016; 4:CD007400. doi: 10.1002/14651858.CD007400.pub3.
  13. Puljak L, Marin A, Vrdoljak D, et al. Celecoxib for osteoarthritis. Cochrane Database Syst Rev. 2017; 5:CD009865. doi: 10.1002/14651858.CD009865.pub2.
  14. Bannuru RR, Schmid CH, Kent DM, et al. Comparative effectiveness of pharmacologic interventions for knee osteoarthritis: A systematic review and network meta-analysis. Ann Intern Med. 2015; 162:46-54. doi: 10.7326/M14-1231.
  15. Bally M, Dendukuri N, Rich B, et al. Risk of acute myocardial infarction with NSAIDs in real world use: Bayesian meta-analysis of individual patient data. BMJ. 2017; 357:j1909. doi: 10.1136/bmj.j1909. 

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