Alternatives to Allopurinol If You Can't Fill Your Prescription

Allopurinol is the first-line urate-lowering therapy recommended by the American College of Rheumatology for gout. But if you're unable to fill your prescription — whether due to a local stock-out, a drug interaction, an allergic reaction, or a side effect — there are proven alternatives your doctor can consider. Here's what you need to know about each option.

Important: Never switch gout medications without consulting your doctor or pharmacist. Some alternatives have different safety profiles, require dose adjustments, or may not be appropriate for your situation.

Why Would Someone Need an Allopurinol Alternative?

There are several scenarios where a patient might need to switch away from allopurinol:

• Local pharmacy stock-out (temporary unavailability)
• Allergic reaction or hypersensitivity (including risk of Stevens-Johnson syndrome in HLA-B*5801-positive patients)
• Drug interactions (e.g., azathioprine, 6-mercaptopurine use)
• Inadequate uric acid control on maximum tolerated allopurinol dose
• Side effects such as rash, nausea, or liver enzyme elevation

Alternative 1: Febuxostat (Uloric) — The Closest Substitute

Febuxostat (brand name Uloric) is the most direct alternative to allopurinol. Like allopurinol, it is a xanthine oxidase inhibitor (XOI) — it works by blocking the same enzyme that produces uric acid. It was FDA-approved in 2009 specifically for gout prevention in patients with hyperuricemia.

When it's preferred: Patients with allopurinol hypersensitivity or intolerance; patients with mild-to-moderate kidney disease who need an easier-to-dose option.

Important caveat: The FDA added a boxed warning to febuxostat in 2019 noting a higher risk of cardiovascular death compared to allopurinol in a clinical trial. Febuxostat is generally avoided in patients with established cardiovascular disease.

Cost: Generic febuxostat is now available and costs roughly $20–$60 per month with coupons, compared to $3–$15 for allopurinol.

Alternative 2: Probenecid — A Uricosuric Option

Probenecid works differently from allopurinol. Instead of blocking uric acid production, it increases uric acid excretion through the kidneys. It has been available since the 1950s and is considered an alternative first-line option by the ACR when XOI therapy is contraindicated.

Best for: Patients under age 60 with normal kidney function and low urinary uric acid excretion.

Not suitable for: Patients with kidney stones, significantly impaired kidney function, or those taking certain antibiotics (probenecid has numerous drug interactions). Requires adequate fluid intake to prevent stone formation.

Drawback: Typically requires two doses per day, compared to allopurinol's once-daily dosing.

Alternative 3: Colchicine (Colcrys) — For Flare Management Only

Colchicine does not lower uric acid levels. It's an anti-inflammatory medication used to treat or prevent acute gout attacks. If you've run out of allopurinol temporarily and experience a flare, colchicine can help manage the pain and inflammation — but it is not a substitute for allopurinol's long-term uric acid lowering effect.

Colchicine is also commonly used alongside allopurinol during the first 3–6 months of starting urate-lowering therapy to prevent the flares that are common when uric acid levels are rapidly dropping.

Alternative 4: Pegloticase (Krystexxa) — For Severe, Refractory Gout

Pegloticase (Krystexxa) is a biologic enzyme that converts uric acid into a compound (allantoin) that the body can easily excrete. It's administered by IV infusion every two weeks and is reserved for patients with severe, chronic gout who have failed all other urate-lowering therapies. It carries a boxed warning for anaphylaxis and infusion reactions.

This is not a routine alternative to allopurinol — it's a last resort for very difficult cases managed by rheumatologists.

Comparing the Alternatives at a Glance

• Febuxostat: Same mechanism as allopurinol, easier renal dosing, but carries cardiovascular risk warning
• Probenecid: Different mechanism (increases excretion), good for normal kidney function, twice daily dosing
• Colchicine: Anti-inflammatory only, does not lower uric acid, good for managing flares during a gap in therapy
• Pegloticase: IV biologic, last resort for refractory gout, expensive and requires medical supervision

What Should I Do Right Now?

Before exploring alternatives, make sure you've genuinely exhausted your options for finding allopurinol. Read our guide on how to find allopurinol in stock near you — many patients find their medication at a nearby pharmacy they hadn't tried. If you've truly hit a wall, call your prescriber's office and explain the situation. They can review your specific medications, kidney function, and medical history to recommend the safest alternative.