Pyrantel induces Ascaris suum muscle contraction, with a pEC 50 of 7.24. Pyrantel produces spastic paralysis of the nematode by selectively gating acetylcholine receptor ion-channels on nerve and muscle. Pyrantel (72 h) inhibits the survival of Ancylostoma ceylanicum , Necator americanus and Trichuris muris on the third-stage larvae (IC 50 s=90.9, 2.0, and 95.5 µg/mL, respectively) and adult worms (IC 50 s=>100, 7.6, and 34.1 µg/mL, respectively).
Pyrantel (10 mg/kg; a single p.o.) reduces the worms in A. ceylanicum -infected hamsters, with the worm burden reduction of 87.2% and worm expulsion rate of 63.4%.