Generic name: Naproxen.

Naprosyn is a nonsteroidal anti-inflammatory drug (NSAID). It works by blocking the production of prostaglandins, which may trigger pain. 

Quick Facts About Naprosyn


Used to relieve inflammation, swelling, stiffness, and joint pain associated with rheumatoid arthritis, juvenile arthritis, osteoarthritis, ankylosing spondylitis (spinal arthritis), tendinitis, bursitis, and acute gout. Also used to relieve menstrual cramps and mild to moderate pain.

Naprosyn Dosage

Take with food or antacid and a full glass of water to avoid stomach irritation. If taking for arthritis, take on regular basis, as prescribed.

  • Usual adult dose: for rheumatoid arthritis, osteoarthritis, and ankylosing spondylitis — 250 milligrams (10 milliliters or 2 teaspoons of suspension), 375 milligrams (15 milliliters or 3 teaspoons), or 500 milligrams (20 milliliters or 4 teaspoons) 2 times per day in the morning and evening. For acute gout — 750 milligrams (30 milliliters or 6 teaspoons), followed by 250 milligrams (10 milliliters or 2 teaspoons) every 8 hours until symptoms are relieved. For mild to moderate pain, menstrual cramps, acute tendinitis and bursitis — 500 milligrams (20 milliliters or 4 teaspoons), followed by 250 milligrams (10 milliliters or teaspoons) every 6 to 8 hours as needed. Maximum dose is 1,250 milligrams (50 milliliters or 10 teaspoons).
  • Usual child dose: for juvenile arthritis — 10 milligrams per 2.2 pounds of body weight, taken 2 times per day. Follow doctor’s instructions carefully for children. Not prescribed for children under 2 years.
  • Missed dose: if on a regular schedule — take as soon as possible, unless almost time for next dose. In that case, do not take missed dose, go back to regular schedule. Do not double doses.

Naprosyn Side Effects

Overdose symptoms:

drowsiness, heartburn, indigestion, nausea, vomiting. If you suspect an overdose, immediately seek medical attention.

More common side effects: abdominal pain, bruising, constipation, difficult or labored breathing, dizziness, drowsiness, headache, heartburn, itching, nausea, ringing in ears, skin eruptions, swelling due to fluid retention.

Less common or rare Naprosyn side effects: abdominal bleeding, black stools, blood in urine, changes in liver function, chills and fever, colitis, congestive heart failure, depression, diarrhea, dream abnormalities, general feeling of illness, hair loss, hearing disturbances or loss, inability to sleep, indigestion, inflammation of lungs, inflammation of mouth, kidney disease or failure, light-headedness, menstrual disorders, muscle pain and weakness, peptic ulcer, red or purple spots on skin, severe allergic reaction, skin inflammation due to sensitivity to light skin rashes, sweating, thirst, throbbing heartbeat, vertigo, visual disturbances, vomiting of blood, yellow skin and eyes.


Inform your doctor before combining Naprosyn with:

aspirin, beta-blockers such as Tenormin, blood thinners such as Coumadin, furosemide (Lasix), lithium (Lithonate), methotrexate, naproxen sodium (Anaprox), phenytoin (Dilantin), probenecid (Benemid), sulfa medications such as Bactrim and Septra, oral diabetes medications such as Diabinese and Micronase.

No known food/other substance interactions.

Special Cautions

If pregnant or planning to become pregnant, inform your doctor immediately. Appears in breast milk; could affect a nursing infant.

No special precautions apply to seniors.

Follow doctor’s instructions carefully for children.

  • May cause drowsiness and impair your ability to drive a car or operate machinery. Do not take part in any activity that requires alertness.
  • You should not take Naprosyn if you have had any reactions to this medication, Anaprox, or similar drugs; or if you have had asthma or nasal inflammation or tumors caused by aspirin or similar medications.
  • Ulcers or internal bleeding can occur without warning; doctor should monitor.
  • Use with caution if you have heart disease, high blood pressure, or kidney or liver disease.
  • May cause vision problems or changes in vision; monitor closely, and report any changes to your doctor.
  • Use with caution if you are taking a blood-thinning medication.
  • Can increase water retention, use cautiously if you have high blood pressure or heart disease.
  • Inform your doctor if you are on a low-sodium diet.

Note: provides accurate and independent information prescription pills, over-the-counter medicines and natural products. This material is provided for educational purposes only and is not intended for medical advice, diagnosis or treatment. If you have questions about  dosage, or Naprosyn side effects, please contact your healthcare provider.