Patients affected by Taenia, Trichuris, Ascaris and Enterobius were treated with 5% Hâ‚‚Oâ‚‚ in the ratio 0.5 l to 4.5 l of boiled water. Adults received per os up to 0.5 l daily, between meals with the recommendation to take it in sips; in children the amount of fluid was reduced to 250 ml of 5% Hâ‚‚Oâ‚‚ daily. In cases with enterobiosis 5% Hâ‚‚Oâ‚‚ solution was given in intrarectal infusions in the amount of 10-100 ml in a single dosis. The duration of the treatment depended on the kind of detected parasites. All cases under treatment showed good therapeutic result. In some cases, nausea or vomiting of transitory type were observed as side-effects of the treatment