Naproxen Uses, Dosage, Side Effects, Food Interaction and all others data.

Naproxen, a propionic acid derivative, is a prototypical NSAID. It reversibly inhibits the cyclooxygenase-1 and -2 (COX-1 and -2) enzymes, thus resulting in reduced synthesis of prostaglandin precursors. It can inhibit platelet aggregation, has anti-inflammatory, analgesic and antipyretic actions.

Naproxen is an established non-selective NSAID and is useful as an analgesic, anti-inflammatory and antipyretic. Similar to other NSAIDs, the pharmacological activity of naproxen can be attributed to the inhibition of cyclo-oxygenase, which in turn reduces prostaglandin synthesis in various tissues and fluids including the synovial fluid, gastric mucosa, and the blood.

Although naproxen is an effective analgesic, it can have unintended deleterious effects in the patient. For instance, naproxen can adversely affect blood pressure control. A study found that use of naproxen induced an increase in blood pressure, although the increase was not as significant as that found with ibuprofen use.

Further, studies have found that the risk of upper gastrointestinal bleeding is on average four-fold higher for individuals taking NSAIDs. Other factors that increase the risk of upper gastrointestinal bleeding include concurrent use of corticosteroids or anticoagulants, and a history of gastrointestinal ulcers.

Trade Name Naproxen
Availability Rx and/or OTC
Generic Naproxen
Naproxen Other Names (S)-Naproxen, Naprolag, Naproxen, Naproxène, Naproxeno, Naproxenum
Related Drugs Humira, Buprenex, aspirin, prednisone, ibuprofen, acetaminophen, tramadol, meloxicam, duloxetine, cyclobenzaprine
Weight 250mg, 500mg,
Type Tablet, Capsule, Liquid Filled
Formula C14H14O3
Weight Average: 230.2592
Monoisotopic: 230.094294314
Protein binding

Naproxen is highly protein bound with >99% of the drug bound to albumin at therapeutic levels.

Groups Approved, Vet approved
Therapeutic Class Drugs for Osteoarthritis, Drugs used for Rheumatoid Arthritis, Non-steroidal Anti-inflammatory Drugs (NSAIDs)
Manufacturer Millinium Pharmaceutical Company, Edruc Ltd, Amico Laboratories Ltd, Organic Health Care, Albion Pharmaceuticals Ltd, Essential Drugs Company Ltd, Guardian Healthcare Ltd, Premier Pharmaceuticals Ltd, Zenith Pharmaceuticals Ltd, Accord-uk Ltd, Ecomed Pharma Limited
Available Country Pakistan, Bangladesh, United Kingdom, United States, Netherlands, Nigeria
Last Updated: September 19, 2023 at 7:00 am


Naproxen is used for the relief of symptoms of rheumatoid arthritis, both of acute flares and long term management of the disease. It is also used in the diseases of rheumatoid osteoarthritis (degenerative arthritis), ankylosing spondylitis, juvenile rheumatoid arthritis, tendinitis, brusitis, acute gout, acute musculoskeletal disorders (such as sprains, direct trauma and fibrositis), migraine and dysmenorrhoea.

Naproxen is also used to associated treatment for these conditions: Acute Gouty Arthritis, Acute Migraine, Ankylosing Spondylitis (AS), Arthritis, Backache, Bursitis, Extra-Articular Rheumatism, Fever, Flu caused by Influenza, Headache, Juvenile Idiopathic Arthritis (JIA), Menstrual Distress (Dysmenorrhea), Migraine, Muscle Spasms, Nasal Congestion, Osteoarthritis (OA), Pain, Post-traumatic pain, Postoperative pain, Primary Dysmenorrhoea, Rheumatoid Arthritis, Rheumatoid Arthritis, Juvenile, Seasonal Allergic Rhinitis, Sinusitis, Tendinitis, Toothache

How Naproxen works

As with other non-selective NSAIDs, naproxen exerts it's clinical effects by blocking COX-1 and COX-2 enzymes leading to decreased prostaglandin synthesis. Although both enzymes contribute to prostaglandin production, they have unique functional differences. The COX-1 enzymes is constitutively active and can be found in normal tissues such as the stomach lining, while the COX-2 enzyme is inducible and produces prostaglandins that mediate pain, fever and inflammation. The COX-2 enzyme mediates the desired antipyretic, analgesic and anti-inflammatory properties offered by Naproxen, while undesired adverse effects such as gastrointestinal upset and renal toxicities are linked to the COX-1 enzyme.


Naproxen dosage

Tablet & Suppository (Adult)-

  • Rheumatic disorders:The usual initial dose of naproxen is 250 mg twice daily adjusted to 500 mg to 1000 mg daily in 2 divided doses.
  • Juvenile arthritis: A dose of 10 mg/kg body weight daily in 2 divided doses is used for children over 5 years of age.
  • Acute gout: An initial dose of 750 mg followed by 250 mg every 8 hours.
  • Dysmenorrhoea: 500 mg may be given initially followed by 250 mg in every 6-8 hours.

Syrup (Children over 5 years)-

  • In juvenile arthritis: The usual dosage of Naproxen is 10 mg/kg/day taken in two doses at 12-hour intervals is recommended.

Gel:Naproxen gel is to be applied 2-6 times a day as required and is not recommended for use in children.

Side Effects

Gastro-intestinal discomfort: nausea, diarrhoea and occasionally bleeding and ulceration.

Hypersensitivity reactions: notably with bronchospasm, rashes and angioedema.

CNS side effect: drowsiness, headache, fluid retention, vertigo, hearing disturbances such as tinnitus, photosensitivity.

A few instances of jaundice, impairment of renal function, thrombocytopenia, and agranulocytosis have been reported.


Although the over-the-counter (OTC) availability of naproxen provides convenience to patients, it also increases the likelihood of overdose. Thankfully, the extent of overdose is typically mild with adverse effects normally limited to drowsiness, lethargy, epigastric pain, nausea and vomiting. Although there is no antidote for naproxen overdose, symptoms will typically subside with appropriate supportive care.

Naproxen is classified as Category B during the first 2 trimesters of pregnancy, and as Category D during the third trimester. Naproxen is contraindicated in the 3rd trimester since it increases the risk of premature closure of the fetal ductus arteriosus and should be avoided in pregnant women starting at 30 weeks gestation.


Naproxen should be used with caution in patients with cardiac, hepatic and renal impairment, coagulation defect, and previous history of gastro-intestinal ulceration. The drug is contraindicated in patients with a history of hypersensitivity to aspirin or any other NSAID - which includes those in whom attacks of asthma, angioedema, urticaria or rhinitis have been precipitated by aspirin or any other NSAID.


Antacid: The absorption of naproxen can be altered by antacids.

Aspirin: Plasma concentration of Naproxen can be reduced when aspirin is given concomitantly, this appeared to be due to increased exeretion of naproxen.

Diuretics: Naproxen diminish the effect of frusemide.

Probenecid: It increase the plasma concentration of Naproxen.

Food Interaction

  • Take with food. Food reduces GI irritation.

Naproxen Alcohol interaction


The concurrent use of aspirin or nonsteroidal anti-inflammatory drugs (NSAIDs) and ethanol may lead to gastrointestinal (GI) blood loss.

The mechanism may be due to a combined local effect as well as inhibition of prostaglandins leading to decreased integrity of the GI lining.

Patients should be counseled on this potential interaction and advised to refrain from alcohol consumption while taking aspirin or NSAIDs.

Naproxen Hypertension interaction

[Major] Fluid retention and edema have been reported in association with the use of nonsteroidal anti-inflammatory drugs (NSAIDs).

Therapy with NSAIDs should be administered cautiously in patients with preexisting fluid retention, hypertension, or a history of heart failure.

Blood pressure and cardiovascular status should be monitored closely during the initiation of NSAID treatment and throughout the course of therapy.

Hypertension interaction

[Moderate] Anaprox and Anaprox DS (brands of naproxen sodium) contain 25 mg and 50 mg of sodium per tablet (approximately 1 mEq<250 mg naproxen), respectively, and Naprosyn suspension contains 39 mg per teaspoonful (approximately 1.5 mEq<125 mg naproxen).

The sodium content should be considered when these products are used in patients with conditions that may require sodium restriction, such as congestive heart failure, hypertension, and fluid retention.

Hypertension interaction

[Moderate] Nonsteroidal anti-inflammatory drugs (NSAIDs), including topicals, can lead to new onset of hypertension or worsening of preexisting hypertension, either of which can contribute to the increased incidence of cardiovascular events.

NSAIDs should be used with caution in patients with hypertension.

Blood pressure should be monitored closely during the initiation of NSAID therapy and throughout the course of therapy.

Volume of Distribution

Naproxen has a volume of distribution of 0.16 L/kg.

Elimination Route

Naproxen is available as a free acid and sodium salt. At comparable doses, (naproxen 500 mg = naproxen sodium 550 mg) they differ slightly in their rates of absorption, but otherwise they are therapeutically and pharmacologically equivalent. Naproxen sodium achieves a peak plasma concentration after 1 hour, while peak plasma concentration is observed after 2 hours with naproxen (free acid). There are no differences between the 2 forms in the post-absorption phase pharmacokinetics. The difference in initial absorption should be considered when treating acute pain, since naproxen sodium may offer a quicker onset of action.

The mean Cmax for the various formulations (immediate release, enteric coated, controlled release etc.) of naproxen are comparable and range from 94 mcg/mL to 97.4 mcg/mL. In one pharmacokinetic study, the mean Tmax of naproxen 500 mg (immediate release) given every 12 hours over 5 days was 3 hours, compared to a mean Tmax of 5 hours for Naprelan 1000 mg (controlled release) given every 24 hours over 5 days. In this same study, the AUC0-24hr was 1446mcgxhr/mL for naproxen immediate release and 1448 mcgxhr/mL for the controlled release formulation. A separate study comparing the pharmacokinetics of Naprosyn tablets and EC-Naprosyn observed the following values: Tmax and AUC0-12hrs of EC-Naprosyn were 4 hours and 845 mcgxhr/mL respectively, and Tmax and AUC0-12hrs values of Naprosyn were 1.9 hours and 767 mcgxhr/mL respectively.

When given in combination with sumatriptan the Cmax of naproxen is roughly 36% lower compared to naproxen sodium 550 mg tablets, and the median Tmax is 5 hours.

Based on the AUC and Cmax of naproxen, Vimovo (naproxen/esomeprazole combination product) and enteric-coated naproxen may be considered bioequivalent.

Overall, naproxen is rapidly and completely absorbed when administered orally and rectally. Food may contribute to a delay in the absorption of orally administered naproxen, but will not affect the extent of absorption.

Half Life

The elimination half-life of naproxen is reported to be 12-17 hours.


Naproxen is cleared at a rate of 0.13 mL/min/kg.

Elimination Route

After oral administration, about 95% of naproxen and it's metabolites can be recovered in the urine with 66-92% recovered as conjugated metabolite and less than 1% recovered as naproxen or desmethylnaproxen. Less than 5% of naproxen is excreted in the feces.

Pregnancy & Breastfeeding use

There are no well controlled studies in pregnant women. The drug should not be used during pregnancy unless clearly needed. Because of the possible adverse effects of prostaglandin inhibiting drugs on neonates, use in nursing mothers must be avoided.


Naproxen suppository in contraindicated in children under 12 years of age. The suppository is contraindicated also in patients with any inflammatory lesions of rectum or anus and in patients with recent history of rectal or anal bleeding.

Acute Overdose

Significant overdosage of the drug may be characterized by drowsiness, heartburn, indigestion, and nausea or vomiting. It is not known what dose of the drug would be life threatening.

Storage Condition

Tablet: Protect from light and store below 30° C temperature in a dry place.

Suppository: Store below 25°C temperature.

Gel: Store in a cool and dry place protected from light.

Innovators Monograph

You find simplified version here Naproxen

Naproxen contains Naproxen see full prescribing information from innovator Naproxen Monograph, Naproxen MSDS, Naproxen FDA label


What is Naproxen used for?

Naproxen is a nonsteroidal anti-inflammatory drug used to treat pain, menstrual cramps, inflammatory diseases such as rheumatoid arthritis, gout and fever. Naproxen is a medicine that reduces inflammation and pain in joints and muscles. It's used to treat diseases of joints, such as rheumatoid arthritis, osteoarthritis and gout.Naproxen also used for period pain and muscle and bone disorders, such as back pain and sprains and strains.

How safe is Naproxen?

Naproxen is safe for occasional use when taken as advised by a doctor. If you have problems with your kidney function, talk to your doctor about the best anti-inflammatory to take. Naproxen may cause an increased risk of sudden kidney failure and even progressive kidney damage.

How does Naproxen work?

Naproxen works by reducing hormones that cause inflammation and pain in the body.

What are the common side effect of Naproxen?

The most common side effects of Naproxen are confusion, headache, ringing in the ears, changes in vision, tiredness, drowsiness, dizziness and rashes. For strains and sprains, some doctors and pharmacists recommend waiting 48 hours before taking naproxen as it may slow down healing.

Is Naproxen safe during pregnancy?

Use of Naproxen during pregnancy is not advised unless prescribed by a doctor, especially if you are 30 or more weeks pregnant.

Will Naproxen affect my fertility?

Naproxen use is not recommended in women attempting to conceive as it may impair female fertility.

Is Naproxen safe during breastfeeding?

Avoid Naproxen, as it can stay in your system longer than ibuprofen and acetaminophen, and never take any aspirin or aspirin-containing products while breastfeeding or pumping.

Can I drink alcohol with Naproxen?

Yes, you can drink alcohol while taking Naproxen. But drinking too much alcohol may irritate your stomach.

Can I drive after taking Naproxen?

You shouldn't drive, use machinery, or do other activities that require alertness until you know you can function normally. 

How fast does Naproxen work?

It is generally around one hour after taking a tablet. It can take up to two hours for you to feel the full effects of the Naproxen dosage you have taken.

When should be taken of Naproxen?

Always take your Naproxen tablets with or just after a meal so you do not get an upset stomach.

Should Naproxen be taken on empty stomach?

You can take Naproxen with or without food. Taking it with food may reduce your risk of upset stomach.

Is Naproxen safe to take daily?

Naproxen take daily generally safe.Adults at first, 1000 milligrams once a day. Some patients may need 1500 mg per day, for a limited period. However, the dose is usually not more than 1000 mg per day.

How long does Naproxen take to work?

You should start to feel better 1 hour after taking Naproxen. But it might take up to 3 days for Naproxen to work properly if you take it regularly twice a day.

How long does Naproxen stay in my system?

Naproxen will be in your system for about 93.5 hours.

Can I take Naproxen for a long time?

It is best to take the lowest dose that works for the shortest possible time.

Who should not take Naproxen?

You should not use Naproxen if you have a history of allergic reaction to aspirin or other NSAID.
Naproxen can increase your risk of fatal heart attack or stroke, especially if you use it long term or take high doses, or if you have heart disease.

What happens if I miss a dose?

Since Naproxen is sometimes used only when needed, you may not be on a dosing schedule. If you are on a schedule, use the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not use extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention.

Can I just stop taking Naproxen?

If you stop taking Naproxen suddenly or don't take it at all: You may experience more pain and inflammation caused by your condition. If you miss doses or don't take Naproxen on schedule: Your medication may not work as well or may stop working completel.
*** Taking medicines without doctor's advice can cause long-term problems.