Which painkillers help in osteoarthritis of the knee?

Photo of a man taking painkillers
PantherMedia / Monkeybusiness Images

Anti-inflammatory painkillers like ibuprofen can relieve pain caused by osteoarthritis. But because they can also have side effects, they should only be taken when needed. It is also best to use them together with other treatments such as exercise therapy.

Pain caused by osteoarthritis can be treated with non-steroidal (NSAIDs). These medications have an inflammation-reducing and pain-relieving effect. Examples of NSAIDs include diclofenac, ibuprofen and naproxen. Two other anti-inflammatory painkillers with a similar effect are celecoxib and etoricoxib. These are (also known as coxibs).

Some NSAIDs can be bought at pharmacies without a prescription – for example, to treat a headache or menstrual pain. But higher doses are sometimes needed to relieve pain effectively in osteoarthritis, and they have to be prescribed by a doctor.

Instead of taking tablets, you can apply an NSAID like diclofenac to your knee as a cream or gel. Studies show that using a cream or gel can effectively relieve the pain, but it needs to be applied 3 to 4 times a day to work.

The drug etofenamate is available in the form of a cream or gel too. But there's no good-quality research on its effectiveness.

How are NSAIDs and coxibs used?

There are a number of different NSAIDs and coxibs. The table below lists the names and doses of the drugs that are most commonly used to relieve osteoarthritis pain:

Drug Typical single dose Maximum daily dose
celecoxib 100 to 200 mg 400 mg
diclofenac 50 to 100 mg (extended release) 150 mg
etoricoxib 30 to 60 mg 60 mg
ibuprofen 400 to 800 mg 2,400 mg
naproxen 250 to 500 mg 1,000 mg

The following is recommended when using painkillers:

  • Do not use painkillers regularly, but only when you need to – for instance, if there are phases of severe pain or during flare-ups.
  • Start at a low dose and stay below the maximum daily dose.
  • Use them in addition to other effective treatments like exercise therapy.
  • Discuss any long-term use with your doctor.

Before taking painkillers, it's also a good idea to check with your doctor or pharmacist whether there are any reasons why you shouldn't use them. Those reasons may include other illnesses that you have or medications you are taking that could interact with the painkillers. You can also find information about that on the medication's package insert.

How effective are NSAIDs and coxibs?

A group of researchers from Switzerland analyzed high-quality studies on the effects of NSAIDs and coxibs in osteoarthritis – a total of more than 70 studies with almost 60,000 participants. The most effective painkillers are diclofenac (150 mg per day) and etoricoxib (60 mg per day).

Researchers from Canada looked into how effectively these painkillers relieve the pain caused by osteoarthritis. Overall, a total of 70 studies with about 28,000 participants showed that the osteoarthritis symptoms improved in

  • 38 out of 100 people who did not use anti-inflammatory painkillers, and in
  • 55 out of 100 people who used anti-inflammatory painkillers.

The studies covered a period of three months. So the medications relieved the symptoms in about 17 out of 100 participants during that time. But medications don't always have the same effect – even in the same person. They might sometimes be more effective, and sometimes less so.

Acetaminophen (paracetamol) was also tested in several studies. But it was not shown to be effective in the treatment of pain caused by osteoarthritis.

How common are side effects and complications?

The most common side effects of anti-inflammatory painkillers are stomach problems. About 10 out of 100 people have mild problems such as indigestion or a stomach ache. These medications are better tolerated when you take them with a meal and plenty of water.

More serious complications like gastritis ( of the stomach lining), ulcers, or bleeding in the stomach or bowel (gastrointestinal bleeding) are less common. The risk of these kinds of complications is greater when they are taken at a higher dose or for a longer time. It also depends on the exact medicine you are using.

Medications for protecting the lining of the stomach like omeprazole or pantoprazole can reduce the risk of these problems and effectively prevent related complications. They do this by lowering the production of acid in the stomach. You can talk with your doctor about when it's a good idea to use these kinds of stomach medications. High doses of NSAIDs and coxibs also increase the risk of cardiovascular (heart and blood vessel) problems such as heart attacks or strokes when used for a long time.

Can you become dependent on NSAIDs and coxibs?

Some people worry too much about the possible risks associated with painkillers. A few worry about becoming dependent on them. But NSAIDs and coxibs don't lead to physical dependence.

Other people worry that taking painkillers might prevent them from feeling warning signs sent by their bodies. There’s no medical reason to worry, though: Chronic pain tells you much less about the condition of your joints than you might think.

What are the possible reasons not to take NSAIDs and coxibs?

Anti-inflammatory painkillers aren't suitable for everyone. You should not take them if you have any of the following health problems:

  • An acute stomach
  • Severe kidney or liver failure
  • Severe heart failure
  • Acute internal bleeding such as bleeding in your stomach
  • Severe dehydration
  • Past allergic reactions to acetylsalicylic acid (the drug in medications like Aspirin) or other painkillers. These might include attacks, allergic skin reactions or symptoms affecting the nose and eyes (e.g. stuffiness and itching)

If you have other medical conditions, you may still be able to use NSAIDs. But it is advisable to speak with a doctor about the pros and cons of NSAIDs and possible alternatives beforehand. For example, this is the case for people who have

  • mild conditions affecting their kidney or liver function,
  • chronic-inflammatory gastrointestinal (stomach and/or bowel) diseases such as or Crohn's disease,
  • risk factors for cardiovascular diseases such as high blood pressure,
  • mild heart failure, or
  • hay fever, nasal or chronic respiratory (airway) diseases.

You should also talk to your doctor first if you are using certain other medications at the same time.

If you have other illnesses or are taking the painkillers for a longer time, your blood and urine will be tested regularly to detect any possible problems early on.

In order to make sure you are using the medication safely, it's also helpful to read the package insert to find out how to use it properly and about the signs of possible complications.

Is the painkiller metamizole (“Novalgin”) an alternative?

Metamizole is a fever-reducing and inflammation-reducing painkiller similar to NSAIDs. There is no research on its effectiveness in the treatment of osteoarthritis, though. Although this drug is often used in Germany, it hasn't been approved for the treatment of osteoarthritis and isn't recommended by medical societies.

The use of metamizole is the subject of debate because it can lead to a rare but very serious side effect known as agranulocytosis. This side effect causes a big drop in the number of certain white blood cells in the body, which can be life-threatening. The possible signs of agranulocytosis include a fever, sore throat, and inflamed mucous membranes. It occurs in far fewer than 1 out of 1,000 people who take metamizole.

Why are opioid painkillers usually not suitable for treating osteoarthritis?

Opioids are prescription painkillers that are used in emergency and intensive care, for instance, to induce anesthesia and to treat cancer-related pain. Morphine is the best-known opioid drug. Other opioids include buprenorphine, codeine, hydromorphone, oxycodone, tapentadol, tilidine and tramadol.

Opioids can relieve acute pain very effectively. But, contrary to popular belief, this is not true for chronic pain: Research has now shown that they also don’t help to relieve osteoarthritis pain any better than NSAIDs do. In fact, the research suggests that their effect is weaker and that it wears off after a few weeks.

So opioids shouldn't be used regularly to treat pain caused by osteoarthritis. They may be an option if several drugs are needed for the short-term treatment of severe pain or to bridge the time until surgery. Opioids are also an option for people who can’t take NSAIDs.

Opioids can have side effects such as constipation, nausea, decreased sex drive, dizziness, tiredness, and affect your ability to drive vehicles. There is also a small risk of a life-threatening overdose. So it is very important to follow the doctor's instructions and not to increase the dose without talking to the doctor first. The same is true for opioid skin patches (fentanyl patches).

If opioids are used, experts advise limiting the treatment to a few weeks or months because they can lead to physical dependence. According to estimates from studies, about 6 out of 100 people become dependent after using them for a longer time.

The use of opioids is not recommended for people who already have a headache disorder, fibromyalgia, inflammation of the pancreas, inflammatory bowel disease or an addiction problem.

Busse JW, Craigie S, Juurlink DN et al. Guideline for opioid therapy and chronic noncancer pain. CMAJ 2017; 189(18): E659-E666.

Da Costa BR, Nüesch E, Kasteler R et al. Oral or transdermal opioids for osteoarthritis of the knee or hip. Cochrane Database Syst Rev 2014; (9): CD003115.

Da Costa BR, Reichenbach S, Keller N et al. Effectiveness of non-steroidal anti-inflammatory drugs for the treatment of pain in knee and hip osteoarthritis: a network meta-analysis. Lancet 2017; 390(10090): e21-e33.

Deutsche Gesellschaft für Orthopädie und Orthopädische Chirurgie (DGOOC). S2k-Leitlinie: Gonarthrose. AWMF-Registernr.: 033-004. 2018.

Fuggle N, Curtis E, Shaw S et al. Safety of Opioids in Osteoarthritis: Outcomes of a Systematic Review and Meta-Analysis. Drugs Aging 2019; 36(Suppl 1): 129-143.

Häuser W, Bock F, Engeser P et al. Long-term opioid use in non-cancer pain. Dtsch Arztebl Int 2014; 111(43): 732-740.

Hurley M, Dickson K, Hallett R et al. Exercise interventions and patient beliefs for people with hip, knee or hip and knee osteoarthritis: a mixed methods review. Cochrane Database Syst Rev 2018; (4): CD010842.

Leopoldino AO, Machado GC, Ferreira PH et al. Paracetamol versus placebo for knee and hip osteoarthritis. Cochrane Database Syst Rev 2019; (2): CD013273.

Machado GC, Abdel-Shaheed C, Underwood M et al. Non-steroidal anti-inflammatory drugs (NSAIDs) for musculoskeletal pain. BMJ 2021; 372: n104.

Osani MC, Lohmander LS, Bannuru RR. Is There Any Role for Opioids in the Management of Knee and Hip Osteoarthritis? A Systematic Review and Meta-Analysis. Arthritis Care Res (Hoboken) 2020 [Epub ahead of print].

Smith SR, Deshpande BR, Collins JE et al. Comparative pain reduction of oral non-steroidal anti-inflammatory drugs and opioids for knee osteoarthritis: systematic analytic review. Osteoarthritis Cartilage 2016; 24(6): 962-972.

Toupin April K, Bisaillon J, Welch V et al. Tramadol for osteoarthritis. Cochrane Database Syst Rev 2019; (5): CD005522.

Welsch P, Petzke F, Klose P et al. Opioids for chronic osteoarthritis pain: An updated systematic review and meta-analysis of efficacy, tolerability and safety in randomized placebo-controlled studies of at least 4 weeks double-blind duration. Eur J Pain 2020; 24(4): 685-703.

IQWiG health information is written with the aim of helping people understand the advantages and disadvantages of the main treatment options and health care services.

Because IQWiG is a German institute, some of the information provided here is specific to the German health care system. The suitability of any of the described options in an individual case can be determined by talking to a doctor. informedhealth.org can provide support for talks with doctors and other medical professionals, but cannot replace them. We do not offer individual consultations.

Our information is based on the results of good-quality studies. It is written by a team of health care professionals, scientists and editors, and reviewed by external experts. You can find a detailed description of how our health information is produced and updated in our methods.

Comment on this page

What would you like to share with us?

We welcome any feedback and ideas. We will review, but not publish, your ratings and comments. Your information will of course be treated confidentially. Fields marked with an asterisk (*) are required fields.

Please note that we do not provide individual advice on matters of health. You can read about where to find help and support in Germany in our information “How can I find self-help groups and information centers?

Updated on August 24, 2021
Next planned update: 2024

Authors/Publishers:

Institute for Quality and Efficiency in Health Care (IQWiG, Germany)

How we keep you informed

Follow us on Twitter or subscribe to our newsletter or newsfeed. You can find all of our films online on YouTube.