Double-blind crossover study of fenquizone compared to chlorthalidone in essential hypertension.

The clinical efficacy and tolerability of fenquizone (10 mg), a thiazide-like diuretic, were studied in comparison with chlorthalidone (25 mg) in 20 hypertensive out-patients during a four-month treatment course. Both drugs were very active in reducing hypertension. Fenquizone proved to be more active on systolic blood pressure, while there were no differences between groups regarding diastolic blood pressure. Chlorthalidone induced a more significant loss of plasma K+ than fenquizone. Fenquizone showed also a significant decrease of symptoms (headache, dizziness) due to hypertension. No undesirable side effects were observed.