In a randomised, double-blind study, the preparation Curbicin, obtained from pumpkin seeds and dwarf palm plants (Cucurbita pepo L. and Sabal serrulata), was compared with a placebo in the treatment of symptoms caused by prostatic hyperplasia; 53 patients took part in the study, which was carried out over a 3-month period. Urinary flow, micturition time, residual urine, frequency of micturition and a subjective assessment of the effect of treatment were all significantly improved in the treatment group. No untoward side effects were noted.