Should allopurinol be started or continued during a gout flare-up?

Allopurinol Use During Gout Flare-Up

When urate-lowering therapy (ULT) is indicated, allopurinol can be initiated during an acute gout flare rather than waiting for the flare to resolve. 1

Starting Allopurinol During a Gout Flare

• The 2020 American College of Rheumatology (ACR) guidelines conditionally recommend starting ULT during a gout flare rather than waiting until after the flare has resolved 1
• The ACR guidelines strongly recommend against delaying ULT initiation until after a flare has resolved 1
• Clinical trials have demonstrated that initiating allopurinol during an acute gout attack does not prolong the duration or severity of the flare 2, 3

Recommendations for Initiating Allopurinol

Dosing

• Start with a low dose (100 mg daily) and gradually increase by 100 mg increments at weekly intervals 4
• Titrate until reaching a serum uric acid level of <6 mg/dL 1, 5
• Patients with renal impairment require lower starting doses:
  • For creatinine clearance 10-20 mL/min: 200 mg daily
  • For creatinine clearance <10 mL/min: ≤100 mg daily 4

Prophylaxis Requirements

• When starting allopurinol (during or after a flare), concomitant anti-inflammatory prophylaxis is strongly recommended 1, 5
• Prophylactic options include:
  • Colchicine (0.6 mg once or twice daily)
  • NSAIDs (e.g., naproxen 250 mg twice daily)
  • Prednisone/prednisolone (if colchicine or NSAIDs are contraindicated) 5, 6
• Continue prophylaxis for 3-6 months after initiating ULT 1, 7

Evidence Supporting Early Initiation

• A randomized clinical trial showed no significant difference in pain scores or flare recurrence when allopurinol was started during an acute gout attack compared to delayed initiation 3
• Another study found no statistically significant difference in days to resolution of acute gout when allopurinol was initiated during the attack (15.4 days vs 13.4 days with placebo, p=0.5) 2
• Both allopurinol and febuxostat have similar flare risk profiles when initiated with appropriate anti-inflammatory prophylaxis 8

Practical Considerations

• Proper prophylaxis significantly reduces the frequency and severity of flares during ULT initiation 7
• Patient education is crucial to explain that any flares during ULT initiation do not indicate treatment failure but rather mobilization of urate crystals 6
• Factors associated with higher flare risk during ULT initiation include younger age, higher baseline serum urate levels, and absence of tophi 8

Common Pitfalls to Avoid

• Waiting for complete resolution of a gout flare before starting allopurinol is no longer recommended and may lead to delayed appropriate therapy 1, 5
• Starting with too high a dose of allopurinol increases flare risk - always begin with 100 mg daily (or lower in renal impairment) 4
• Failing to provide adequate anti-inflammatory prophylaxis when initiating ULT 5, 7
• Discontinuing ULT if a flare occurs during treatment initiation 5

By initiating allopurinol during a gout flare with appropriate prophylaxis, you can begin addressing the underlying hyperuricemia sooner without prolonging the acute attack, ultimately improving long-term outcomes for gout patients.