Naproxen

Is naproxen safe?

At the dose on the pack and for a few days, yes, for most adults. Naproxen is the NSAID in Aleve and in prescription brands such as Naprosyn and Anaprox. It eases pain and swelling for 8 to 12 hours per dose, which is why people with arthritis, gout or period pain often prefer it.

It carries the same boxed warningBoxed warningThe strongest safety warning the US FDA puts on a medicine's label, printed inside a black border at the top.More in the glossary as every prescription NSAID: heart attack and stroke, and stomach or bowel bleeding that can be fatal and can come without warning. Its profile differs from ibuprofen in one useful way and one less helpful one. Trials suggest a lower heart risk, but the stomach risk is at least as high and the drug lingers longer. We score it 73, one point below ibuprofen at 74.

The heart question

Naproxen is the NSAID most often called the "heart-friendlier" choice, and the evidence behind that is real but limited. In 2013 the Coxib and traditional NSAID Trialists' Collaboration pooled individual data from 754 randomised trials in The Lancet. High-dose diclofenac and the coxibs raised major vascular events by about a third. High-dose naproxen did not raise them at all (rate ratio 0.93, with a confidence interval from 0.69 to 1.27). The MHRA had already said in 2012 that naproxen and low-dose ibuprofen have the most favourable heart profiles of the older NSAIDs.

The US label is more cautious. It says it is unclear whether the heart risk is the same for all NSAIDs and keeps the boxed warningBoxed warningThe strongest safety warning the US FDA puts on a medicine's label, printed inside a black border at the top.More in the glossary for naproxen. Every NSAID in that analysis, naproxen included, roughly doubled the risk of heart failure. If you have heart disease, high blood pressure or a past stroke, no NSAID is a casual choice; ask your doctor which painkiller suits you.

Stomach bleeding: the bigger risk with naproxen

The same Lancet analysis found that high-dose naproxen raised serious upper stomach complications (bleeding, perforation, obstruction) about fourfold compared with placebo, similar to high-dose ibuprofen and higher than diclofenac or the coxibs. The FDA label gives the class figures: about 1% of patients have an ulcer, bleed or perforation after 3 to 6 months, and 2% to 4% after a year. Only one in five has warning symptoms first.

Because naproxen's half-life is 12 to 17 hours, it reaches steady levels after 4 to 5 days and keeps working on the stomach lining between doses. The Aleve label lists who is most at risk:

• people aged 60 or over
• anyone who has had a stomach ulcer or bleeding problem
• people taking a blood thinner such as warfarin, or a steroid
• people taking another NSAID, including aspirin or ibuprofen
• people who have three or more alcoholic drinks a day

Black or tarry stools, vomiting blood or stomach pain that does not ease need urgent medical attention.

Doses: Aleve versus prescription naproxen

Product	Label dose	Maximum
Aleve, 220 mg naproxen sodium (US)	1 tablet every 8 to 12 hours; 2 allowed for the first dose	2 in any 8 to 12 hours, 3 in 24 hours
Naproxen tablets (prescription)	250, 375 or 500 mg twice a day	1,500 mg a day for up to 6 months
Naproxen sodium 550 mg (prescription)	550 mg every 12 hours for acute pain	1,375 mg naproxen sodium on day one, then 1,100 mg

Two points cause most mistakes. First, naproxen and naproxen sodium are dosed differently (220 mg of the sodium salt contains 200 mg of naproxen). Second, the label warns against taking two naproxen products at once, because they all become the same active form in the blood. The over-the-counterOver-the-counterA medicine you can buy without a prescription, in a pharmacy or shop, with directions on the pack for safe use without a doctor.More in the glossary limits are 10 days for pain and 3 days for fever without a doctor. In the UK the NHS says not to take naproxen bought without a prescription for more than 3 days.

Kidneys, blood pressure and interactions

NSAIDs cut blood flow to the kidneys. That rarely matters in a healthy adult, but it can cause kidney injury in someone who is dehydrated, older, or taking a diuretic plus an ACE inhibitor or ARB such as lisinopril. The label also warns that naproxen can raise lithium levels (by about 15% on average), increase methotrexate toxicity and blunt the effect of blood pressure drugs.

One interaction is specific to naproxen. Even 220 mg once or twice a day interfered with the anti-clotting effect of low-dose aspirin in a study cited on the label, and the effect was strongest as naproxen wore off. If you take aspirin for your heart, ask your pharmacist how to fit any painkiller around it.

Who should be careful

Talk to your doctor or pharmacist before using naproxen if you are pregnant (the FDA and MHRA warn against NSAIDs from 20 weeks), have asthma that reacts to aspirin, or have kidney, liver or heart disease. The same applies if you have had a recent heart attack or take lithium, methotrexate, an SSRI or a blood thinner. Stop and get help for a rash with blisters or peeling; the label added fixed drug eruption to its skin warnings in November 2024.

An overdose is rarely fatal but can cause stomach bleeding and, rarely, kidney failure or coma. Call Poison Control on 1-800-222-1222 in the US or NHS 111 in the UK, especially for children.

How we scored it

Dependence (97), track record (95) and overdose marginOverdose marginHow far a normal dose is from a harmful one. A wide margin means an accidental extra dose is unlikely to cause serious harm.More in the glossary (85) are strong. Serious side effects (63) score a little below ibuprofen because of naproxen's long action and high stomach bleeding rate, partly offset by better heart data. Regulatory warnings (45) reflect the boxed warningBoxed warningThe strongest safety warning the US FDA puts on a medicine's label, printed inside a black border at the top.More in the glossary shared by all prescription NSAIDs. A lower score is no reason to stop a medicine your doctor prescribed.