Do NOT use Naprosyn if:

• you are allergic to any ingredient in Naprosyn
• you have had a severe allergic reaction (eg, severe rash, hives, trouble breathing, growths in the nose, dizziness) to aspirin or a nonsteroidal anti-inflammatory drug (NSAID) (eg, ibuprofen, celecoxib)
• you have recently had or will be having bypass heart surgery
• you are in the last 3 months of pregnancy

Contact your doctor or health care provider right away if any of these apply to you.

Some medical conditions may interact with Naprosyn. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:

• if you are pregnant, planning to become pregnant, or are breast-feeding
• if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
• if you have allergies to medicines, foods, or other substances
• if you have a history of kidney or liver disease, diabetes, or stomach or bowel problems (eg, bleeding, perforation, ulcers)
• if you have a history of swelling or fluid buildup, asthma, growths in the nose (nasal polyps), or mouth inflammation
• if you have high blood pressure, blood disorders, bleeding or clotting problems, heart problems (eg, heart failure), or blood vessel disease, or if you are at risk for any of these diseases
• if you have poor health, dehydration or low fluid volume, or low blood sodium levels, you are on a low salt (sodium) diet, you drink alcohol, or you have a history of alcohol abuse.

Some medicines may interact with Naprosyn. Tell your health care provider if you are taking any other medicines, especially any of the following:

• Anticoagulants (eg, warfarin), aspirin, corticosteroids (eg, prednisone), heparin, or selective serotonin reuptake inhibitors (SSRIs) (eg, fluoxetine) because the risk of stomach bleeding may be increased
• Probenecid because it may increase the risk of Naprosyn's side effects
• Cyclosporine, hydantoins (eg, phenytoin), lithium, methotrexate, quinolones (eg, ciprofloxacin), sulfonamides (eg, sulfamethoxazole), or sulfonylureas (eg, glipizide) because the risk of their side effects may be increased by Naprosyn
• Angiotensin-converting enzyme (ACE) inhibitors (eg, enalapril), beta-blockers (eg, propranolol), or diuretics (eg, furosemide, hydrochlorothiazide) because their effectiveness may be decreased by Naprosyn.

This may not be a complete list of all interactions that may occur. Ask your health care provider if Naprosyn may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.

Important safety information:

• Naprosyn may cause dizziness or drowsiness. These effects may be worse if you take it with alcohol or certain medicines. Use Naprosyn with caution. Do not drive or perform other possible unsafe tasks until you know how you react to it.
• Serious stomach ulcers or bleeding can occur with the use of Naprosyn. Taking it in high doses or for a long time, smoking, or drinking alcohol increases the risk of these side effects. Taking Naprosyn with food will NOT reduce the risk of these effects. Contact your doctor or emergency room at once if you develop severe stomach or back pain; black, tarry stools; vomit that looks like blood or coffee grounds; or unusual weight gain or swelling.
• Do not take more than the recommended dose or use for longer than prescribed without checking with your doctor.
• Naprosyn has naproxen in it. Before you start any new medicine, check the label to see if it has naproxen or any other NSAID (eg, ibuprofen) in it too. If it does or if you are not sure, check with your doctor or pharmacist.
• Do not take aspirin while you are using Naprosyn unless your doctor tells you to.
• Do not switch between different forms of Naprosyn (eg, tablets, suspension) unless your doctor tells you to. They may not provide the same amount of medicine to your body.
• Naprosyn may interfere with certain lab tests. Be sure your doctor and lab personnel know that you take Naprosyn.
• Lab tests including kidney function, complete blood cell counts, and blood pressure, may be performed while you use Naprosyn. These tests may be used to monitor your condition or check for side effects. Be sure to keep all doctor and lab appointments.
• Use Naprosyn with caution in the elderly; they may be more sensitive to its effects, especially stomach bleeding and kidney problems.
• Naprosyn should be used with extreme caution in children younger than 2 years old; safety and effectiveness in these children have not been confirmed.
• Pregnancy and breast-feeding: Naprosyn may harm the fetus. Do not use it during the last 3 months of pregnancy. If you think you may be pregnant, contact your doctor. You will need to discuss the benefits and risks of using Naprosyn while you are pregnant. Naprosyn should not be used during labor. Naprosyn is found in breast milk. Do not breastfeed while taking Naprosyn.

All medicines may cause side effects, but many people have no, or minor, side effects.

Check with your doctor if any of these most common side effects persist or become bothersome:

Constipation; diarrhea; dizziness; drowsiness; gas; headache; heartburn; nausea; stomach upset; stuffy nose.

Seek medical attention right away if any of these severe side effects occur:

Severe allergic reactions (rash; hives; itching; trouble breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); bloody or black, tarry stools; change in the amount of urine produced; chest pain; confusion; dark urine; depression; fainting; fast or irregular heartbeat; fever, chills, or persistent sore throat; mental or mood changes; numbness of an arm or leg; one-sided weakness; red, swollen, blistered, or peeling skin; ringing in the ears; seizures; severe headache or dizziness; severe or persistent stomach pain or nausea; severe vomiting; shortness of breath; sudden or unexplained weight gain; swelling of hands, legs, or feet; unusual bruising or bleeding; unusual joint or muscle pain; unusual tiredness or weakness; vision or speech changes; vomit that looks like coffee grounds; yellowing of the skin or eyes.

This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider.