OverviewDosageSide EffectsInteractionsHalf-Life

Generic Name: Naproxen sodium
Brands: Aleve, Anaprox DS, Mediproxen, Flanax (naproxen), All Day Pain Relief, Wal-Proxen, Naprelan CR, All Day Relief, Comfort Pac-Naproxen, Ec-Naprosyn
Class: Nonsteroidal anti-inflammatory drug (NSAID)
Availability: Over the counter
Molecular Formula: C14H14O3
Substance UNII: 57Y76R9ATQ

What is Naproxen?

Naproxen is a nonsteroidal anti-inflammatory drug (NSAID). It is often sold under the brand names Aleve, Naprosyn, Anaprox, and Naproxen Sodium DS. It is available over the counter (OTC) and is prescription grade. 

What Is Naproxen Used For?

Naproxen is used to treat pain, reduce fever, and control menstrual cramps. It is also often part of a care plan to manage inflammatory conditions such as rheumatoid arthritis (RA), osteoarthritis, and ankylosing spondylitis (Bechterew’s disease), as well.  

How Does Naproxen Work?

Naproxen inhibits certain enzymes, specifically COX-1 and COX-2. As a result, it prevents the body from synthesizing (creating) prostaglandins, compounds that have hormone-like effects. 

Prostaglandins work as signaling molecules, so the exact effect depends on the receptor. They can increase sensitivity to pain, induce inflammation, and promote uterine cramping. By inhibiting the production of these compounds, Naproxin therefore has an anti-inflammatory effect.

How Long Does it Take for Naproxen to Work?

It will depend on which formulation (whether it is the long acting or short acting) someone is using it for and what effect they are hoping for. For normal pain relief and fever reduction, it should take about 45 minutes for the short acting (non EC or DR formulations). For long-term effects against arthritis, it may take up to one week to show best benefits. 

Do Not Use Naproxen if:

There are several situations where this medication may not be the right choice for you. According to the U.S. National Library of Medicine, the following should not use naproxen sodium:

  • Anyone with a previous allergic reaction to pain medication or fever reducers
  • Anyone preparing for heart surgery

Please note that this list may not be complete, and there may be other situations where naproxen use is not advisable.

Ask a doctor before using naproxen if there are incidents of bleeding in the stomach, a history of heartburn, a diagnosis of high blood pressure or disease of the heart, liver, or kidneys. 

IMPORTANT NOTE: Speak with your physician before taking naproxen with any oral anti coagulation or anti platelet medication since naproxen can increase risk of bleeding. Some of these medications include: Apixaban (Eliquis), Rivaroxaban (Xarelto), Dabigatran (Pradaxa), Warfarin (Jantoven), Clopidogrel (Plavix) , Ticagrelor (Brilinta), etc.

Naproxen Pill Imprints

List of the most popular Naproxen pill imprints.

*This is not an exhaustive list

Naproxen IP 190 500

Naproxen IP 190 500 Pill Imprint white oval

Drug: Naproxen
Strength: 500 mg
Pill Imprint: IP 190 500
Color: White
Shape: Elliptical / Oval

Naproxen G 32 500

Drug: Naproxen
Strength: 500 mg
Pill Imprint: G 32 500
Color: Orange
Shape: Capsule-shape

Naproxen Sodium L368

Drug: Naproxen Sodium
Strength: 220 mg
Pill Imprint: L368
Color: Blue
Shape: Elliptical / Oval

Naproxen I G 342

Drug: Naproxen
Strength: 500 mg
Pill Imprint: I G 342
Color: Yellow
Shape: Capsule-shape

Naproxen G32 375

Drug: Naproxen
Strength: 375 mg
Pill Imprint: G32 375
Color: Pink
Shape: Elliptical / Oval

Naproxen 140

Drug: Naproxen
Strength: 500 mg
Pill Imprint: 140
Color: White
Shape: Capsule-shape

Disclaimer: this article does not constitute or replace medical advice. If you have an emergency or a serious medical question, please contact a medical professional or call 911 immediately. To see our full medical disclaimer, visit our Terms of Use page.

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