EN
Rats (176) aged 4-6 months, infected with 300 or 1500 Trichinella spiralis larvae, were given prednisone (Encorton, Polfa) by oral route in the daily dosis of 1mg for 6 consecutive days one or two weeks after the infection. A part of animals received encorton for 6 days prior to infection. The effect of the drug was evaluated on the basis of the number of mature forms at 7 and 15 days after the infection and of larval forms in the 7-10th week of invasion. It was found that changes induced by encorton in the parasitologic picture of invasion were comparable to those described for cortizone. The action of encorton is of short duration and disappears as the drug is discontinued.