Relafen Indication:

For acute and chronic treatment of signs and symptoms of osteoarthritis and rheumatoid arthritis.

Relafen Mechanism Of Action:

The parent compound is a prodrug, which undergoes hepatic biotransformation to the active component, 6-methoxy-2-naphthylacetic acid (6MNA), that is a potent inhibitor of prostaglandin synthesis, most likely through binding to the COX-1 and COX-2 receptors.

Relafen Drug Interactions:

Alendronate Increased risk of gastric toxicity
Methotrexate The NSAID increases the effect and toxicity of methotrexate
Cyclosporine Monitor for nephrotoxicity
Anisindione The NSAID increases the anticoagulant effect
Warfarin The NSAID increases the anticoagulant effect
Acenocoumarol The NSAID increases the anticoagulant effect
Dicumarol The NSAID increases the anticoagulant effect

Relafen Food Interactions:

Avoid alcohol.
Take with food.

Relafen Generic Name:


  • Nabumetonum [INN-Latin]
  • Nabumetona

Drug Type:

Small Molecule; Approved


Well absorbed from the gastrointestinal tract. Coadministration of food increases the rate of absorption and subsequent appearance of 6MNA (the active metabolite) in the plasma but does not affect the extent of conversion of nabumetone into 6MNA.

Toxicity (Overdose):

The one overdose occurred in a 17-year-old female patient who had a history of abdominal pain and was hospitalized for increased abdominal pain following ingestion of 30 nabumetone tablets (15 grams total). Stools were negative for occult blood and there was no fall in serum hemoglobin concentration. The patient had no other symptoms.

Protein Binding:

The active metabolite, 6MNA, is more than 99% bound to plasma proteins.


Undergoes rapid biotransformation to the principal active metabolite, 6-methoxy-2-naphthylacetic acid (6MNA). Approximately 35% of a 1000 mg oral dose of nabumetone is converted to 6MNA and 50% is converted into unidentified metabolites which are subsequently excreted in the urine.

Half Life:

Approximately 23 hours for the active metabolite, 6MNA. Increased in patients with renal insufficiency.

Dosage Forms of Relafen:

Tablet Oral

Chemical IUPAC Name:


Organisms Affected:

Humans and other mammals

Relafen to general, pharmacology

General, pharmacology..