Randomized, Double-Blind Clinical Trial to Assess the Acute Diuretic Effect of Equisetum arvense (Field Horsetail) in Healthy Volunteers.

In this double-blind, randomized clinical trial, 36 healthy male volunteers were randomly distributed into three groups (n = 12) that underwent a three-step treatment. For four consecutive days, we alternately administered a standardized dried extract of Equisetum arvense (EADE, 900 mg/day), placebo (corn starch, 900 mg/day), or hydrochlorothiazide (25 mg/day), separated by a 10-day washout period. Each volunteer served as his own control, and the groups' results were compared.