Medical Author: Omudhome Ogbru, Pharm.D.
Medical Editor: Jay Marks, M.D.

GENERIC NAME: naproxen

BRAND NAME: Anaprox, Naprelan, Naprosyn, Aleve

DRUG CLASS AND MECHANISM: Naproxen belongs to a class of drugs called nonsteroidal antiinflammatory drugs (NSAIDs). Other members of this class include ibuprofen (Motrin), indomethacin (Indocin), nabumetone (Relafen) and several others. These drugs are used for the management of mild to moderate pain, fever, and inflammation. They work by reducing the levels of prostaglandins, chemicals that are responsible for pain, fever, and inflammation. Naproxen blocks the enzyme that makes prostaglandins (cyclooxygenase), resulting in lower concentrations of prostaglandins. As a consequence, inflammation, pain and fever are reduced. Naproxen was approved by the FDA in December 1991.

PRESCRIPTION: Yes; (Aleve, no)

GENERIC AVAILABLE: Yes

PREPARATIONS:

• Anaprox (tablets): 275 and 550 mg;
• Naprosyn (tablets): 250, 375, and 500 mg;
• Naprosyn suspension: 125 mg/5ml;
• EC-Naprosyn: 375 mg,
• Aleve: 220 mg;
• Naprelan (controlled-release tablets): 375 and 500mg.

STORAGE: Naproxen should be stored at room temperature: 15-30 C (59-86 F).

PRESCRIBED FOR: Naproxen is used for the treatment of mild to moderate pain, inflammation, and fever.

DOSING: The usual adult dose is 250-500 mg twice daily using regular naproxen tablets. The usual dose for Naprelan controlled release tablets is 750 to 1000 mg given once daily. For EC-Naprosyn, the usual dose is 375-500 mg twice daily. Naproxen should be given with food to reduce upset stomach.

DRUG INTERACTIONS: Naproxen is associated with several suspected or probable interactions that affect the action of other drugs. The following examples are the most common suspected interactions.

Naproxen may increase the blood levels of lithium (Eskalith) by reducing the excretion of lithium by the kidneys. Increased levels of lithium may lead to lithium toxicity.

Naproxen may reduce the blood pressure lowering effects of blood pressure medications. This may occur because prostaglandins play a role in the regulation of blood pressure.

When naproxen is used in combination with methotrexate or aminoglycosides (for example, gentamicin) the blood levels of the methotrexate or aminoglycoside may increase, presumably because the elimination from the body is reduced. This may lead to more methotrexate or aminoglycoside-related side effects.

Individuals taking oral blood thinners or anticoagulants [for example, warfarin, (Coumadin)] should avoid naproxen because naproxen also thins the blood, and excessive blood thinning may lead to bleeding.

PREGNANCY: There are no adequate studies of naproxen in pregnant women. Therefore, naproxen is not recommended during pregnancy.

NURSING MOTHERS: A small amount of naproxen is excreted in breast milk. Because the concentration in breast milk is low, breastfeeding while taking naproxen probably is not harmful to the infant.

SIDE EFFECTS: The most common side effects from naproxen are rash, ringing in the ears, headaches, dizziness, drowsiness, abdominal pain, nausea, diarrhea, constipation, heartburn, fluid retention and shortness of breath.

NSAIDs reduce the ability of blood to clot and therefore increase bleeding after an injury. Naproxen also may cause stomach and intestinal bleeding and ulcers. Sometimes, stomach ulceration and intestinal bleeding can occur without any abdominal pain. Black tarry stools, weakness, and dizziness upon standing may be the only signs of the bleeding.

People who are allergic to other NSAIDs should not use naproxen. NSAIDs reduce the flow of blood to the kidneys and impair function of the kidneys. The impairment is most likely to occur in patients with preexisting impairment of kidney function or congestive heart failure, and use of NSAIDs in these patients should be done cautiously. Individuals with asthma are more likely to experience allergic reactions to naproxen and other NSAIDs. Fluid retention, blood clots, heart attacks, hypertension, and heart failure have also been associated with the use of NSAIDs.