Chlorthalidone-Induced Gout Flares

Mechanism and Risk

• Chlorthalidone can directly precipitate gout flares by elevating serum uric acid levels and reducing renal uric acid excretion, making it a well-established trigger for acute gouty arthritis in susceptible patients 1, 2
• The American College of Cardiology and the American Heart Association caution to "use with caution in patients with history of acute gout unless patient is on uric acid-lowering therapy" 1, 2
• The European League Against Rheumatism identifies diuretics as a key risk factor that should be searched for in every person with gout 4

Management and Treatment

• The American College of Rheumatology conditionally recommends switching chlorthalidone to an alternate antihypertensive when feasible, such as losartan, which has unique uricosuric effects that actively lower serum uric acid 3
• The European League Against Rheumatism specifically recommends losartan for hypertension management in gout patients 5
• Calcium channel blockers are an alternative option as they do not adversely affect uric acid levels 5, 3

Critical Considerations

• Chlorthalidone is preferred over hydrochlorothiazide for cardiovascular outcomes based on prolonged half-life and proven trial reduction of CVD 1, 2
• In patients with established cardiovascular disease or heart failure, discontinuation of chlorthalidone may not be appropriate 3