Should allopurinol (xanthine oxidase inhibitor) be continued during a gout flare?

Allopurinol Should Be Continued During a Gout Flare

Allopurinol should be continued during an acute gout flare rather than being discontinued, as this approach is supported by current guidelines and does not prolong the duration of the flare. 1

Evidence-Based Rationale

• The 2020 American College of Rheumatology (ACR) guidelines for gout management conditionally recommend starting urate-lowering therapy (ULT) during a gout flare rather than waiting until the flare has resolved, based on moderate certainty of evidence 1
• This recommendation indicates that not only can allopurinol be initiated during a flare, but by extension, it should be continued if already started 1
• Research shows that starting allopurinol during an acute gout attack does not prolong the duration of the treated attack compared to placebo 2

Management Algorithm During Gout Flares

Continue Allopurinol + Provide Acute Flare Treatment

• Continue existing allopurinol dose without interruption 1
• Treat the acute flare with appropriate anti-inflammatory therapy:
  • Colchicine, NSAIDs, or corticosteroids based on patient factors 1
  • The choice of anti-inflammatory agent should be individualized based on comorbidities and contraindications 1

Dose Adjustments During Flares

• If the patient is already on allopurinol, maintain the current dose 1
• If initiating allopurinol during a flare, start at a low dose (≤100 mg/day, lower in patients with CKD) 1
• Continue the treat-to-target strategy with gradual dose titration to achieve serum urate <6 mg/dL 1

Prophylaxis Recommendations

• For patients starting or continuing allopurinol, anti-inflammatory prophylaxis is strongly recommended 1
• Continue prophylaxis for 3-6 months with ongoing evaluation 1
• Options for prophylaxis include:
  • Low-dose colchicine (0.6 mg once or twice daily) 3
  • Low-dose NSAIDs (e.g., naproxen 250 mg twice daily) 4
  • Low-dose corticosteroids if colchicine or NSAIDs are contraindicated 4

Common Pitfalls to Avoid

• Discontinuing allopurinol during flares: This traditional practice is not supported by current evidence and may disrupt the treat-to-target strategy 1, 2
• Inadequate prophylaxis: Failure to provide adequate anti-inflammatory prophylaxis when starting or continuing ULT increases flare risk 3
• Intermittent allopurinol therapy: Studies show that intermittent allopurinol therapy is less effective than continuous therapy for controlling gout symptoms 5
• Stopping ULT once symptoms resolve: The ACR guidelines conditionally recommend continuing ULT indefinitely rather than stopping it, as discontinuation often leads to recurrence of flares 1

Risk Factors for Flares During Allopurinol Treatment

• Recent gout flare in the month before starting allopurinol (OR 2.65) 6
• Starting at allopurinol 100 mg dose (OR 3.21) compared to lower doses 6
• Serum urate ≥0.36 mmol/L at 6 months (OR 2.85) 6

By continuing allopurinol during gout flares while providing appropriate anti-inflammatory treatment, you can maintain progress toward the long-term goal of lowering serum urate levels without prolonging the acute attack.