Naproxen belongs to a class of drugs called non-steroidal anti-inflammatory drugs, or NSAIDs, which are used to reduce pain and inflammation. It can be taken by most adults, although you should speak to your doctor before taking the drug if you are over the age of 65 or pregnant. Naproxen is not recommended for children under 2 years.

Although naproxen is generally considered safer than certain other drugs (like steroids and narcotics) that can be used to treat similar health conditions, some patients have experienced adverse side effects. In some cases, these side effects have been life threatening.

Uses of Naproxen

Naproxen is an NSAID available in prescription-strength dosages and over-the-counter (OTC) brands, such as Aleve and Anaprox. It is primarily used to relieve pain, stiffness, swelling, and tenderness. It may also be taken to reduce a fever.

Naproxen may be used to treat the symptoms of the following conditions:

  • Acute gout
  • Ankylosing spondylitis (arthritis of the spine)
  • Backaches
  • Bursitis
  • Juvenile arthritis
  • Osteoarthritis
  • Rheumatoid arthritis
  • Menstrual pain
  • Mild headaches
  • Muscle aches
  • Shoulder pain
  • Tendinitis
  • Toothaches

Generic and brand name naproxen medications are available. Brand name naproxen medications include:

  • Aflaxen
  • Aleve
  • Anaprox
  • Mediproxen
  • Naprelan
  • Naprosyn

For adults, the maximum daily dose of naproxen is approximately 1,000 milligrams (mg). This varies depending on the nature of the condition you are taking the drug to treat, your age, and how long you have been taking naproxen. Speak to your doctor to find out the dosage that’s right for you.

How Naproxen Works

Naproxen works by temporarily preventing your body from releasing a substance called prostaglandin, which contributes to inflammation and may cause pain and fever. By blocking prostaglandins, naproxen can relieve minor aches and pains.

Since the pain relief achieved by taking the drug lasts longer than other NSAIDs in its class, naproxen is often the best option for treating both minor temporary pain and pain resulting from chronic conditions.

Common Side Effects of Naproxen

The following side effects of naproxen are common and rarely serious. Call your doctor if any of these symptoms persist or become severe.

Naproxen Side Effects
  • Burning or tingling in appendages
  • Cold symptoms
  • Constipation
  • Diarrhea
  • Difficulty sleeping or staying asleep
  • Dizziness
  • Drowsiness
  • Gas
  • Excessive thirst
  • Headache
  • Hearing problems
  • Heartburn
  • Lightheadedness
  • Ringing in ears

Serious Naproxen Side Effects

When taken as directed, naproxen is generally considered safe to use. In some cases, side effects can occur after both limited and extended use. Possible side effects of naproxen include:

Ulcers, bleeding, or holes in the stomach or intestine

Serious gastrointestinal (GI) problems can sometimes occur with the use of naproxen. Problems may develop suddenly at any time during treatment, and can be fatal. At greatest risk are those taking NSAIDs for extended periods of time, those who are elderly or in poor health, and those who consume three or more alcoholic drinks per day while taking naproxen.

In 2005, the U.S. Food and Drug Administration (FDA) issued a relabeling request to all sponsors of marketed prescription and OTC NSAIDs. This required the professional labeling for all prescription NSAIDs to include a boxed warning highlighting the potential increased risk of serious adverse GI bleeding, and for non-prescription forms of the drug to include more specific information about GI risks.

Heart attack and stroke

Patients who take NSAIDs like naproxen may have a higher risk of experiencing a heart attack or a stroke than those who do not take these medications.The FDA issued a boxed warning in December 2004 after the National Institute of Health (NIH) halted a clinical trial which found that the risk of heart attack and stroke was twice as high in patients taking two tablets a day for three years. The FDA requires the professional labeling of all prescription NSAIDs to include the risk of cardiovascular (CV) events. The labeling for nonprescription NSAIDs must also include more specific information about potential CV risks.

Kidney damage

A 2009 study of long-distance runners who took NSAIDs like naproxen before a race to prevent muscle soreness found that this increased the likelihood of developing temporary kidney failure. In 2015, five studies published in the European Journal of Internal Medicine reported an increased risk of acute kidney injury ranging from 58% to 211% among NSAID users.

Liver damage

Naproxen-associated liver toxicity is rare, but has been shown in patients with cholestasis and hepatitis shortly after taking the drug. The resulting liver damage can take years to resolve, and may be irreversible.

Increased risks in pregnant women

A 2012 study found that the use of NSAIDs in early pregnancy does not appear to increase a woman’s risk of complications. However, there were a few moderate connections between NSAIDs use during pregnancy and specific birth defects in children, including:

  • Amniotic band syndrome
  • Clubfoot
  • Anophthalmia and microphthalmia
  • Cleft lip and cleft palate
  • Spina bifida

It’s recommended that women avoid NSAIDs during pregnancy. Researchers have suggested taking acetaminophen instead, which works through a different mechanism than this drug class and is generally considered safe for use during pregnancy.

Other Serious Side Effects

Furthermore, if you experience any of the following severe symptoms, stop taking naproxen and seek medical attention immediately.

  • Blisters or skin rashes (Stevens Johnson Syndrome)
  • Blood in the stool, or black and tarry stools
  • Chest pain
  • Stomach pain
  • Shortness of breath
  • Slurred speech
  • Vomit that is bloody or has appearance of coffee grounds
  • Weakness in one part or side of the body

These side effects may happen suddenly and have the potential to result in death.

Do not take naproxen if you have heart disease or have had a heart attack, unless your doctor instructs you to. Be sure to tell your doctor if you or anyone in your family has or has ever had a heart attack, stroke, or heart disease. Before taking naproxen, you should also inform your doctor if you smoke, or if you have or have ever had diabetes, high cholesterol, or high blood pressure. These conditions can increase your risk of more serious complications.

Depending on your condition, you may experience other side effects not listed here. Be mindful of your body’s response to the drug, and seek medical assistance if you experience severe adverse effects.

Naproxen Drug Interactions

Some medicines can affect how naproxen works. Before taking naproxen, inform your doctor if you take any of the following:

Although prescription-strength naproxen and its OTC counterparts like Aleve are safe to use for most people, it’s wise to take precaution and talk to your doctor if you have any concerns about the risks.

Naproxen Lawsuits

There are no class-action lawsuits related to naproxen pending at this time. If you or someone you love has experienced health issues due to the FDA’s delayed warnings about CV and GI risks, speak to a lawyer to find out what’s right for you.