Pyrantel is a worm medicine in suspension or tablet form, used mainly in children against roundworm, pinworm and hookworm. It paralyses the worms, which are then naturally expelled in the stool.
Also known as: Pamoato de pirantel, Pin-X
No documented drug–drug interactions for this medicine.
Pyrantel acts within the intestinal lumen and systemic absorption is minimal — food does not interfere clinically.
Take with or without food.
Prontuário Terapêutico INFARMED, 1.4.2 (pyrantel — luminal pharmacokinetics).
Pyrantel is hepatically metabolised — caution in liver disease.
Consider alternatives in severe liver disease.
Prontuário Terapêutico INFARMED, 1.4.2 (pyrantel — hepatic pharmacokinetics).
Annex 1 records "Avoid" (factor C). Low systemic absorption; use only if clearly necessary and if the alternative (mebendazole) is not suitable.
Avoid; defer deworming treatment until after pregnancy if possible.
Milk excretion poorly characterised; low systemic absorption makes the theoretical risk small — compatible with caution.
Prontuário Terapêutico INFARMED — Annex 1: "Pyrantel — Avoid" (l. 41331). EMC-UK — Pyrantel SmPC (in countries with registration).
Clinical and educational support tool. The information does not replace a medical prescription or the opinion of a qualified healthcare professional.
First-line paediatric luminal anthelmintic against intestinal nematodes (Ascaris, Enterobius, hookworms); acts by spastic paralysis of the worm in the lumen, expelled by peristalsis.
Agonist of nematode neuromuscular nicotinic receptors: persistent and irreversible depolarisation of worm muscle, spastic paralysis and expulsion. Inactive against eggs and tissue-migrating larvae.
Poorly absorbed orally (6–17%); plasma peak 1–3 h; administration with food does not significantly change luminal efficacy. The pamoate salt is poorly soluble, keeping the drug in the intestine.
Hepatic metabolism to N-methyl-pyrantel (main inactive metabolite); absorbed fraction excreted in urine (7–17% as N-methyl). No relevant CYP interactions described.
~1–3 h (absorbed fraction, renally excreted as N-methyl); the unabsorbed fraction is eliminated in faeces.
Medicines from the same therapeutic group (ATC classification) or the same pharmacological class.
