What is nabumetone used for?

Nabumetone is used to treat the signs and symptoms of osteoarthritis and rheumatoid arthritis.

Can nabumetone cause heart problems?

Yes, nabumetone can increase the risk of serious heart-related events like heart attack and stroke, which can be fatal.

Will nabumetone upset my stomach?

Stomach issues are common with nabumetone, including diarrhea, indigestion, and abdominal pain.

Is it safe to take nabumetone if I have had asthma?

You should not take nabumetone if you have had asthma, hives, or allergic reactions after taking aspirin or other NSAIDs.

Can I take nabumetone while pregnant?

You should avoid nabumetone during pregnancy, particularly after 20 weeks, due to risks of fetal kidney issues and heart duct complications.

How much nabumetone should I take?

The typical starting dose is 1,000 mg daily, but a doctor may adjust this between 1,000 mg and 2,000 mg per day.

Does nabumetone interact with blood pressure medicine?

Yes, nabumetone may make certain blood pressure medicines (ACE-Inhibitors) less effective.

What happens if I take too much nabumetone?

An overdose might cause drowsiness, nausea, or vomiting, and in rare cases, kidney failure or coma.

Nabumetone | CAS 42924-53-8 | BLXXJMDCKKHMKV

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Non-steroidal anti-inflammatory drug (NSAID)

Nabumetone (brand name Relafen) is a non-steroidal anti-inflammatory drug (NSAID) used to relieve pain and swelling from osteoarthritis and rheumatoid arthritis. It works by blocking certain enzymes that cause inflammation. Because it is a prodrug, your body converts it into its active form, 6-methoxy-2-naphthylacetic acid (6MNA), after you swallow it.

How it worksNabumetone is a prodrug that turns into an active substance called 6MNA in your liver. This active substance works by inhibiting prostaglandin synthesis to reduce inflammation and pain.

Brand names:RELAFEN

Used for

Osteoarthritis reliefRheumatoid arthritis relief

Conditions

OsteoarthritisRheumatoid arthritis

Class

NSAIDAnti-InflammatoryAnalgesicAntipyreticNon-steroidal anti-inflammatory drug (NSAID)GastrointestinalCentral Nervous SystemDermatologicSpecial SensesRenalCardiovascular

How to take

FormsOral tablet

RoutesOral

The usual starting dose is 1,000 mg taken once daily, with or without food. Depending on how you respond, a doctor may adjust the dose between 1,000 mg and 2,000 mg per day. It can be taken as a single dose or split into two doses. For patients weighing less than 50 kg, doses higher than 1,000 mg may not be necessary.

Always use the lowest effective dose for the shortest amount of time needed to meet your treatment goals.

Key warnings

Nabumetone carries two major warnings: 1. It can increase the risk of serious heart problems like heart attack and stroke, which can be fatal. This risk can happen early in treatment and may increase with longer use. 2. It can increase the risk of serious stomach or intestinal issues like bleeding, ulcers, and holes in the digestive tract, which can be fatal. These can happen at any time without warning, and elderly patients are at higher risk.

·Nabumetone carries two major warnings: 1. It can increase the risk of serious heart problems like heart attack and stroke, which can be fatal. This risk can happen early in treatment and may increase with longer use. 2. It can increase the risk of serious stomach or intestinal issues like bleeding, ulcers, and holes in the digestive tract, which can be fatal. These can happen at any time without warning, and elderly patients are at higher risk.
·Increased risk of serious cardiovascular events like heart attack and stroke.
·Increased risk of serious gastrointestinal bleeding, ulceration, and perforation.
·Do not use nabumetone if you are having coronary artery bypass graft (CABG) surgery.
·Risk of kidney issues, especially when used with certain diuretics.

Do not use if

·Known allergy to nabumetone or any of its ingredients.
·History of asthma, hives, or allergic reactions after taking aspirin or other NSAIDs.
·Use during or immediately after coronary artery bypass graft (CABG) surgery.

Side effects

Common

DiarrheaIndigestionStomach painConstipationGasNauseaDry mouthDizzinessHeadacheFatigueInsomniaNervousnessRashSwelling (edema)

Serious

·Heart attack or stroke
·Stomach bleeding, ulcers, or holes in the stomach/intestines
·Severe allergic reactions (anaphylaxis)
·Kidney problems
·Severe skin reactions
·Liver problems

Seek help if

·Severe stomach pain
·Black or bloody stools
·Chest pain
·Shortness of breath
·Sudden weakness or numbness
·Severe skin rash

Interactions

·ACE-Inhibitors: Nabumetone may reduce the blood pressure-lowering effects of these drugs.
·Aspirin: Taking aspirin with nabumetone may reduce how much aspirin binds to proteins; using them together is generally not recommended due to increased side effect risks.
·Diuretics (like furosemide or thiazides): Nabumetone may reduce the effect of these water pills and increase the risk of kidney failure.
·Lithium: Nabumetone can increase lithium levels in your blood, which could be dangerous.
·Other NSAIDs: Interactions reported with Mobic, Rimadyl, Lodine, Elyxyb, Vioxx, Bextra, Licart, and Coxanto.

FoodCan be taken with or without food.

Special populations

PregnancyAvoid using nabumetone during pregnancy, especially around 20 weeks gestation (due to potential fetal kidney issues) and 30 weeks gestation or later (due to the risk of premature closure of the fetal ductus arteriosus).

BreastfeedingIt is not known if nabumetone passes into human milk. Because of the potential for serious reactions in nursing babies, you should talk to your doctor about whether to stop breastfeeding or stop taking the medication.

PediatricThe safety and effectiveness of nabumetone in children have not been established.

GeriatricUse caution when treating adults aged 65 and older, as is standard with all NSAIDs.

Talk to your doctor

Monitor

·Signs of stomach bleeding
·Signs of heart attack or stroke
·Kidney function
·Blood pressure
·Lithium levels

Questions to ask

·Should I avoid nabumetone if I have heart disease?
·Will this interact with my blood pressure medicine?
·Is it safe to take nabumetone with my current arthritis medications?
·How long should I take the lowest effective dose?

Pharmacokinetics

BioavailabilityNabumetone is well absorbed from the gastrointestinal tract; approximately 80% of a radiolabeled dose is found in the urine.

Protein bindingThe active metabolite 6MNA is more than 99% bound to plasma proteins.

MetabolismNabumetone is a prodrug that undergoes hepatic biotransformatiom to the active component, 6-methoxy-2-naphthylacetic acid (6MNA).

ExcretionApproximately 80% of a radiolabeled dose is found in the urine. 6MNA and unidentified metabolites are excreted in the urine.

Practical

OverdoseOverdose symptoms can include sleepiness, nausea, vomiting, stomach pain, and diarrhea. Serious but rare complications include high blood pressure, kidney failure, breathing problems, and coma. There is no specific antidote; treatment focuses on supportive care.

Ingredients

Allergens

none

Inactive

colloidal silicon dioxidecorn starchhypromellosemagnesium stearatepovidonesodium lauryl sulfatesodium starch glycolatetitanium dioxidetriacetintalciron oxide red

Educational summary derived from FDA labeling, AI-assisted. Not medical advice — consult a healthcare professional. Updated 2026-04-25.