Nabumetone Shortage: What Providers and Prescribers Need to Know in 2026

Patients with osteoarthritis and rheumatoid arthritis who rely on nabumetone may occasionally present to your office or call your staff reporting difficulty filling their prescription. While nabumetone is not currently on the FDA's official drug shortage list, pharmacy-level availability gaps are a real and recurring challenge. This guide provides a clinical framework for managing these situations effectively in 2026.

Current Availability Status: What the Data Shows

As of 2026, nabumetone is not listed on the FDA Drug Shortages Database or the ASHP Drug Shortages Resource Center. Generic nabumetone (500 mg, 750 mg, and 1,000 mg tablets) is manufactured by multiple domestic and international suppliers. The 1,000 mg strength is also available as Relafen DS. However, the original Relafen brand has been discontinued, and with lower overall prescription volume — approximately 800,000 fills per year — individual pharmacy stocking can be inconsistent, particularly for the 500 mg and 750 mg strengths.

Clinical Pharmacology Reminder: Why Patients Choose Nabumetone

Nabumetone's profile as a non-acidic NSAID prodrug is clinically meaningful for certain patients. The parent compound undergoes first-pass hepatic biotransformation to its active metabolite, 6-methoxy-2-naphthylacetic acid (6MNA), which preferentially inhibits COX-2 over COX-1. This pharmacokinetic property results in lower topical gastric irritation compared to traditional acidic NSAIDs, as the drug exerts no direct mucosal contact with gastric lining before hepatic conversion.

For patients with osteoarthritis who have mild GI sensitivity but do not meet criteria for PPI co-therapy or COX-2 selective agents, nabumetone may represent an appropriate middle-ground choice. Its once or twice-daily dosing also supports adherence in older patients managing complex regimens.

Therapeutic Substitution: Evidence-Based Alternatives

When nabumetone is unavailable and a therapeutic substitute is needed, consider the following options based on clinical context:

Meloxicam (Mobic) 7.5–15 mg once daily: Structurally similar to nabumetone in its COX-2 preference, meloxicam is an FDA-approved, widely available, and inexpensive generic. Most appropriate first-line therapeutic substitute in patients without contraindications.

Celecoxib (Celebrex) 100–200 mg twice daily: Preferred for patients with higher GI risk (prior ulcer, anticoagulant use) or who have responded better to selective COX-2 inhibition. Available generically. Note sulfonamide allergy cross-reactivity considerations.

Naproxen sodium 550 mg twice daily: Appropriate for patients with lower cardiovascular risk. Less GI-friendly than nabumetone but widely available and low cost. Some data suggests slightly lower cardiovascular thromboembolic risk compared to other NSAIDs.

Diclofenac sodium 75–100 mg daily: Consider topical diclofenac gel (1%) for localized osteoarthritis (knee, hand) to minimize systemic exposure.

Patients Who Should NOT Be Switched Without Careful Review

Some patients on nabumetone may have been specifically selected for it due to comorbidities or prior NSAID intolerance. Before any substitution, review:

History of GI events on other NSAIDs (nabumetone may have been chosen for its lower GI irritation profile)

Renal function — all NSAIDs require caution with CrCl below 30 mL/min; nabumetone has a specific dose reduction guideline

Concurrent anticoagulation (warfarin, DOACs) — all NSAIDs increase GI bleeding risk; no NSAID is safe without monitoring in these patients

Cardiovascular history — all NSAIDs carry boxed warning for cardiovascular events; ensure risk-benefit is re-evaluated at any transition

How to Help Patients Find Nabumetone in Stock

Before substituting, it is worth helping patients locate their medication. medfinder for providers is a service that calls pharmacies on a patient's behalf to locate available stock, then texts the patient results. Directing patients to medfinder or advising them to request a special order from their pharmacy (typically fulfilled in 1–2 business days) often resolves the issue without requiring a prescription change.

Prescribing Considerations for 2026

When writing for nabumetone, specify the strength clearly — 500 mg, 750 mg, or 1,000 mg — to help pharmacies identify stock quickly.

Consider writing a 90-day quantity for stable patients to reduce refill frequency and avoid localized stock issues.

Advise patients to begin refill search 7–10 days before running out, not on the last day of their supply.

Ensure patients know that Relafen DS (1,000 mg) is still a brand option if their dose is 1,000 mg and generic is unavailable at their pharmacy.

Summary for Clinical Practice

Nabumetone availability challenges are manageable with proactive strategies. Directing patients to tools like medfinder, enabling 90-day supplies, and having a pre-vetted substitution plan (meloxicam first, then celecoxib or naproxen based on GI/CV risk) reduces interruptions to care. See our related guide: how to help your patients find nabumetone.