Chlorthalidone works better than hydrochlorothiazide for lowering blood pressure.
Thiazide diuretics are recommended as part of initial therapy for uncomplicated hypertension. Blood pressure guidelines currently lump all thiazides together...with the assumption that they are equally effective.
Most prescribers will reach for hydrochlorothiazide. "HCTZ" is easy to write for and it's available in many combo products.
But some experts contend that chlorthalidone is the better drug.