Pyrantel: Uses, Side Effects, Warnings, Recommendations and Mechanism of Action

It is a medicine used to treat a number of parasitic worm infections.

This includes ascariasis, hookworm infections, enterobiasis ( pinworm infection ), trichostrongyliasis, and trichinellosis. It is taken orally.

Side effects

Side effects include nausea, headache, dizziness, trouble sleeping, and a rash. A lower dose should be used in people with liver disease.

While it does not appear to be harmful during pregnancy, it has not been studied for this use. It is not clear if it is safe to use while breastfeeding.

It is in the family of anthelmintic drugs .

Pyrantel was first described in 1965. It is on the World Health Organization’s Essential Medicines List, the most effective and safest medicines needed in a healthcare system.

Pyrantel is available as a generic drug. It costs less than $ 25 per course of treatment in the United States. It can also be used to treat worms in various other animals.

Warnings and Recommendations

Pyrantel pamoate is considered a pregnancy category C drug for use during pregnancy in humans, but is in category A for canines and felines.

Pyrantel is considered safe to use in nursing animals.

Mechanism of action

Pyrantel pamoate acts as a depolarizing neuromuscular blocking agent, causing a sudden contraction, followed by paralysis, of the helminths.

This has the result of causing the worm to “lose its grip” on the intestinal wall and pass out of the system by a natural process.

Since pyrantel is poorly absorbed by the host’s gut, the host is not affected by the small dose of medication used. Spastic (tetanus) paralyzing agents, particularly pyrantel pamoate, can induce complete intestinal obstruction in a heavy worm load.

This obstruction usually takes the form of a worm impaction and occurs when a very small, but heavily parasitized animal is treated and attempts to pass a large number of dislodged worms at once.

The worms generally pass in normal stools or with occasional diarrhea, straining, and vomiting.