Ficus glabrata latex has been a well-known anthelminthic remedy in the neotropical regions since ancient times. The latex has been commercially exploited for decades because of its content of the proteolytic enzyme complex ficin. A safe dosage regimen with direct use of the latex has been elucidated to control intestinal helminthiasis in the Indian and non-Indian rural population. Helminthiasis was common in three Amazonian villages, field bases for the clinical study, with an overall prevalence of 92%. Specific prevalences were: Ascaris 68%, Strongyloides 42%, Trichuris 41%, Ancylostoma/ Necator 26% and Taenia 1%. Variation in the biological activity of the latex was estimated by using a milk coagulating test. Pharmacological studies with live Ascaris demonstrated a lethal effect at concentrations down to 0.05% latex in physiological saline solution. A clinical trial on 181 persons has resulted in a recommended dosage of 1.0 cm3 of prepared latex kg per day for 3 days to be repeated every 3 months. © 1986.