Nabumetone

Mechanism-of-action class: Cyclooxygenase Inhibitors.

• Carefully consider the potential benefits and risks of nabumetone tablets and other treatment options before deciding to use nabumetone tablets. Use the lowest effective dose for the shortest duration consistent with individual patient treatment goals (see WARNINGS ).

• Nabumetone tablets are contraindicated in patients with known hypersensitivity to nabumetone or product excipients. Nabumetone tablets should not be given to patients who have experienced asthma, urticaria, or allergic-type reactions after taking aspirin or other NSAIDs.contraindicated

Carefully consider the potential benefits and risks of nabumetone tablets and other treatment options before deciding to use nabumetone tablets. Use the lowest effective dose for the shortest duration consistent with individual patient treatment goals (see WARNINGS ). After observing the response to initial therapy with nabumetone tablets, the dose and frequency should be adjusted to suit an individual patient's needs. Osteoarthritis and Rheumatoid Arthritis The recommended starting dose is 1,000 mg taken as a single dose with or without food. Some patients may obtain more symptomatic relief from 1,500 mg to 2,000 mg per day. Nabumetone tablets can be given in either a single or twice-daily dose. Dosages greater than 2,000 mg per day have not been studied. The lowest effective dose should be used for chronic treatment (see WARNINGS , Renal Effects ). Patients weighing under 50 kg may be less likely to require dosages beyond 1,000 mg; therefore, after observing the response to initial therapy, the dose should be adjusted to meet individual patients' requirements.

Cardiovascular Effects Cardiovascular Thrombotic Events Clinical trials of several COX-2 selective and nonselective NSAIDs of up to three years duration have shown an increased risk of serious cardiovascular (CV) thrombotic events, including myocardial infarction (MI) and stroke, which can be fatal. Based on available data, it is unclear that the risk for CV thrombotic events is similar for all NSAIDs. The relative increase in serious CV thrombotic events over baseline conferred by NSAID use appears to be similar in those with and without known CV disease or risk factors for CV disease. However, patients with known CV disease or risk factors had a higher absolute incidence of excess serious CV thrombotic events, due to their increased baseline rate. Some observational studies found that this increased risk of serious CV thrombotic events began as early as the first weeks of treatment. The increase in CV thrombotic risk has been observed most consistently at higher doses. To minimize the potential risk for an adverse CV event in NSAID-treated patients, use the lowest effective dose for the shortest duration possible. Physicians and patients should remain alert for the development of such events, throughout the entire treatment course, even in the absence of previous CV symptoms. Patients should be informed about the symptoms of serious CV events and the steps to take if they occur. There is no consistent evidence that concurrent use of aspirin mitigates the increased risk of serious CV thrombotic events associated with NSAID use.

Adverse reaction information was derived from blinded-controlled and open-labeled clinical trials and from worldwide marketing experience. In the description below, rates of the more common events (greater than 1%) and many of the less common events (less than 1%) represent results of U.S. clinical studies. Of the 1,677 patients who received nabumetone during U.S. clinical trials, 1,524 were treated for at least 1 month, 1,327 for at least 3 months, 929 for at least a year, and 750 for at least 2 years. More than 300 patients have been treated for 5 years or longer. The most frequently reported adverse reactions were related to the gastrointestinal tract and included diarrhea, dyspepsia, and abdominal pain. Incidence ≥ 1% - Probably Causally Related Gastrointestinal Diarrhea (14%), dyspepsia (13%), abdominal pain (12%), constipation *2 , flatulence *2 , nausea *2 , positive stool guaiac *2 , dry mouth, gastritis, stomatitis, vomiting. Central Nervous System Dizziness *2 , headache *2 , fatigue, increased sweating, insomnia, nervousness, somnolence. Dermatologic Pruritus *2 , rash *2 . Special Senses Tinnitus *2 . Miscellaneous Edema *2 . * 2 Incidence of reported reaction between 3% and 9%. Reactions occurring in 1% to 3% of the patients are unmarked. Incidence < 1% - Probably Causally Related †3 Gastrointestinal Anorexia, jaundice, duodenal ulcer, dysphagia, gastric ulcer, gastroenteritis, gastrointestinal bleeding, increased appetite, liver function abnormalities, melena, hepatic failure .

Fetal Toxicity Premature Closure of Fetal Ductus Arteriosus : Avoid use of NSAIDs, including nabumetone tablets, in pregnant women at about 30 weeks gestation and later. NSAIDs including nabumetone tablets, increase the risk of premature closure of the fetal ductus arteriosus at approximately this gestational age. Oligohydramnios/Neonatal Renal Impairment : Use of NSAIDs, including nabumetone tablets, at about 20 weeks gestation or later in pregnancy may cause fetal renal dysfunction leading to oligohydramnios and, in some cases, neonatal renal impairment. These adverse outcomes are seen, on average, after days to weeks of treatment, although oligohydramnios has been infrequently reported as soon as 48 hours after NSAID initiation. Oligohydramnios is often, but not always, reversible with treatment discontinuation. Complications of prolonged oligohydramnios may, for example, include limb contractures and delayed lung maturation. In some postmarketing cases of impaired neonatal renal function, invasive procedures such as exchange transfusion or dialysis were required. If NSAID treatment is necessary between about 20 weeks and 30 weeks gestation, limit nabumetone tablets use to the lowest effective dose and shortest duration possible. Consider ultrasound monitoring of amniotic fluid if nabumetone tablets treatment extends beyond 48 hours.

Metabolism

After oral administration, approximately 80% of a radiolabeled dose of nabumetone is found in the urine, indicating that nabumetone is well absorbed from the gastrointestinal tract. Nabumetone itself is not detected in the plasma because, after absorption, it undergoes rapid biotransformation to the principal active metabolite, 6-methoxy-2-naphthylacetic acid (6MNA).

Symptoms following acute NSAIDs overdoses are usually limited to lethargy, drowsiness, nausea, vomiting, and epigastric pain, which are generally reversible with supportive care. Gastrointestinal bleeding can occur. Hypertension, acute renal failure, respiratory depression, and coma may occur, but are rare. Anaphylactoid reactions have been reported with therapeutic ingestion of NSAIDs, and may occur following an overdose. Patients should be managed by symptomatic and supportive care following a NSAIDs overdose. There are no specific antidotes. Emesis and/or activated charcoal (60 to 100 grams in adults, 1 to 2 g/kg in children), and/or osmotic cathartic may be indicated in patients seen within 4 hours of ingestion with symptoms or following a large overdose (5 to 10 times the usual dose). Forced diuresis, alkalinization of urine, hemodialysis, or hemoperfusion may not be useful due to high protein binding. There have been overdoses of up to 25 grams of nabumetone reported with no long-term sequelae following standard emergency treatment (i.e., activated charcoal, gastric lavage, IV H 2 -blockers, etc.).

• Feb 25, 2002ANDAANDA075280Chartwell Rx
• Mar 7, 2008ANDAANDA078671Invagen Pharms
• Sep 24, 2008ANDAANDA078420Sciegen Pharms
• Jan 12, 2011ANDAANDA090445Annora Pharma
• Jun 13, 2011ANDAANDA091083Watson Labs
• Aug 30, 2019ANDAANDA203166Lgm Pharma
• Jan 7, 2025ANDAANDA219118Novitium Pharma

1. 1Drug Ineffective5037.9%
2. 2Pain4637.3%
3. 3Nausea3755.9%
4. 4Fatigue3615.7%
5. 5Headache3205.0%
6. 6Arthralgia3094.9%
7. 7Dyspnoea2443.8%
8. 8Diarrhoea2413.8%
9. 9Pain In Extremity2263.6%
10. 10Dizziness2253.5%
11. 11Chronic Kidney Disease2233.5%
12. 12Anxiety2103.3%
13. 13Fall2083.3%
14. 14Acute Kidney Injury1993.1%
15. 15Back Pain1973.1%

Recent PubMed references pinned to Nabumetone as a MeSH major topic. Citations link to pubmed.ncbi.nlm.nih.gov.

• Radiolytic Elimination of Nabumetone from Aqueous Solution: Degradation Efficiency, and Degradants' Toxicity.
  Molecules (Basel, Switzerland) · 2024 · Tartaro Bujak I, Klarić D, Lučić B, et al.
  PMID 39795121DOI 10.3390/molecules30010064
• Toward Multitasking Pharmacological COX-Targeting Agents: Non-Steroidal Anti-Inflammatory Prodrugs with Antiproliferative Effects.
  Molecules (Basel, Switzerland) · 2021 · Grande F, Giordano F, Occhiuzzi MA, et al.
  PMID 34203324DOI 10.3390/molecules26133940
• Nabumetone induced photogenotoxicity mechanism mediated by ROS generation under environmental UV radiation in human keratinocytes (HaCaT) cell line.
  Toxicology and applied pharmacology · 2021 · Qureshi S, Chandra S, Chopra D, et al.
  PMID 33798594DOI 10.1016/j.taap.2021.115516
• Presence or absence of microbiome modulates the response of mice organism to administered drug nabumetone.
  Physiological research · 2020 · Jourová L, Lišková B, Lněničková K, et al.
  PMID 33646003DOI 10.33549/physiolres.934607
• Useful alternative drugs before the use of opioids in patients with allergy to NSAIDs.
  Rheumatology (Oxford, England) · 2021 · Barranco R, Alava C, Garcia-Moguel I, et al.
  PMID 33590849DOI 10.1093/rheumatology/keab165
• Role of human flavin-containing monooxygenase (FMO) 5 in the metabolism of nabumetone: Baeyer-Villiger oxidation in the activation of the intermediate metabolite, 3-hydroxy nabumetone, to the active metabolite, 6-methoxy-2-naphthylacetic acid in vitro.
  Xenobiotica; the fate of foreign compounds in biological systems · 2021 · Matsumoto K, Hasegawa T, Ohara K, et al.
  PMID 33146575DOI 10.1080/00498254.2020.1843089
• Design of a pseudo stir bar sorptive extraction using graphenized pencil lead as the base of the molecularly imprinted polymer for extraction of nabumetone.
  Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy · 2020 · Afsharipour R, Dadfarnia S, Shabani AMH, et al.
  PMID 32388234DOI 10.1016/j.saa.2020.118427
• A metabolic pathway for the prodrug nabumetone to the pharmacologically active metabolite, 6-methoxy-2-naphthylacetic acid (6-MNA) by non-cytochrome P450 enzymes.
  Xenobiotica; the fate of foreign compounds in biological systems · 2020 · Matsumoto K, Hasegawa T, Ohara K, et al.
  PMID 31855101DOI 10.1080/00498254.2019.1704097

The 8 most recently updated of 8 ClinicalTrials.gov registrations naming Nabumetone as an intervention. Registration is not evidence of efficacy or safety — reference crosswalk only.

• Effect of the Bioheat Patch on Pain Following the HyFoSy Procedure
  Not yet recruiting · Interventional · 80 enrolled · Assaf-Harofeh Medical Center
  NCT07081971updated 2025-07-30
• Acute Appendicitis: Active Observation With and Without Antibiotics
  Completed · Phase 4 · Interventional · 126 enrolled · Göteborg University
  NCT03985514updated 2022-08-16
• Single Dose Two-Way Crossover Fed Bioequivalence Study of Nabumetone 750 mg Tablets in Healthy Volunteers
  Completed · Phase 1 · Interventional · 30 enrolled · Actavis Inc.
  NCT00864604updated 2020-01-07
• To Compare the Efficacy and Safety of LAYLA in Osteoarthritis Patients of the Knee
  Completed · Phase 4 · Interventional · 134 enrolled · PMG Pharm Co., Ltd
  NCT02049606updated 2017-09-20
• The Effect on Knee Joint Loads of Analgesic Use Compared With Exercise in Patients With Knee Osteoarthritis - An RCT
  Completed · Interventional · 93 enrolled · University of Southern Denmark
  NCT01638962updated 2016-08-03
• Single Dose Two-Way Crossover Fasted Bioequivalence Study of Nabumetone 750 mg Tablets in Healthy Volunteers
  Completed · Phase 1 · Interventional · 40 enrolled · Actavis Inc.
  NCT00864968updated 2010-08-17
• Bioequivalence Study of Nabumetone 750 mg Tablets of Dr. Reddy's Under Fed Conditions
  Completed · Phase 1 · Interventional · 30 enrolled · Dr. Reddy's Laboratories Limited
  NCT01164826updated 2010-07-19
• Bioequivalence Study of Nabumetone 750 mg Tablets of Dr. Reddy's Under Fasting Conditions
  Completed · Phase 1 · Interventional · 44 enrolled · Dr. Reddy's Laboratories Limited
  NCT01164813updated 2010-07-19

CPIC-curated drug–gene pairs for Nabumetone. Levels describe the strength of curated evidence and guideline status — never a recommendation to test or to adjust therapy.

• CYP2C9CPIC C
  CYP2C9 and NSAIDs

Frequently asked questions

How does Nabumetone work?

Mechanism-of-action class: Cyclooxygenase Inhibitors.

What is Nabumetone used for?

According to FDA labeling, Nabumetone carries indications including: Carefully consider the potential benefits and risks of nabumetone tablets and other treatment options before deciding to use nabumetone tablets. Use the lowest effective dose for the shortest duration consistent with individual patient treatment goals (see WARNINGS ).. This is a reference summary of labeled uses, not medical advice or a treatment recommendation.

What class of drug is Nabumetone?

Nabumetone is classified as Other antiinflammatory and antirheumatic agents, non-steroids, Nonsteroidal Anti-inflammatory Drug, Cyclooxygenase Inhibitors, Decreased Platelet Activating Factor Production, Decreased Prostaglandin Production, Decreased Renal K+ Excretion, Decreased Renal Na+ Excretion, Decreased Thromboxane Production.

What are the brand names for Nabumetone?

Nabumetone is marketed under brand names including Relafen.

What are the contraindications for Nabumetone?

Nabumetone labeling lists contraindications including: Nabumetone tablets are contraindicated in patients with known hypersensitivity to nabumetone or product excipients. Nabumetone tablets should not be given to patients who have experienced asthma, urticaria, or allergic-type reactions after taking aspirin or other NSAIDs.. Always consult the full prescribing information and a clinician.