Pyrantrin is a brand of pyrantel pamoate worm expeller with a broad spectrum anthelmintic activity against commonly occurring intestinal worms. Pyrantrin is suitable for the treatment of infestation with any of the following gastrointestinal parasites when these are present either alone or as a mixed infestation. Indication: Hook worms Round worms Pin worms Thread worms Whip worms Pyrantrin causes instant depolarizing neuromuscular blockade activity thus leading to rapid paralysis of the worm.