Gout drug allopurinol is safe to keep escalating — even with mild liver enzyme bumps

Physicians treating gout can breathe a little easier: a new prospective study published in Arthritis Care & Research confirms that escalating allopurinol doses is safe even when patients show mild-to-moderate elevations in liver enzymes (AST/ALT). This has been a gray area in clinical practice, since liver enzyme elevation is a commonly cited adverse event in allopurinol trials — occurring in 2%–10% of patients — and has sometimes led to dose reduction or discontinuation.

Researchers from Singapore's National University Hospital followed 150 gout patients newly started on allopurinol for a median of ~33 weeks. Among the 20% who developed elevated liver enzymes, the vast majority of cases were mild, and none progressed to severe elevation. Crucially, allopurinol dose itself was not linked to enzyme rises — alcohol consumption and statin non-use were the real drivers.

Key Takeaways

• 20% of patients developed elevated AST/ALT during follow-up, but 86.7% of cases were mild and none were severe
• Alcohol use was a strong independent predictor of liver enzyme elevation (adjusted OR = 3.52)
• Statin use appeared protective against enzyme elevation (adjusted OR = 3.41 for non-users)
• Higher allopurinol doses were not associated with increased liver enzyme risk

Why it matters: Many clinicians hesitate to push allopurinol to target doses when they see liver enzyme blips — but this study suggests that's often unnecessary caution. Managing lifestyle factors like alcohol and addressing comorbidities may be more impactful than pulling back on the medication itself.