Pyrantel is an anthelmintic agent. It is active against Enterobius vermicularis, Ascaris lumbricoіdes, Anсylostoma duodenale and Necator americanus. Pyrantel causes neuromuscular blockade, paralyzing the helminthes, so that they are excreted by intestinal peristalsis with feces. Pyrantel is active against sensitive sexually mature and immature helminthes. Larvae, which migrate via tissues, are not affected.
Intestinal resorption of Pyrantel is very low. After the intake of the drug, its plasma concentration is very low (0.05-0.13 µg/ml) and reaches its peak within 1-3 hours. Up to 93% of the drug is excreted with feces intact. Less than 7% is detected in the urine intact and in form of metabolites.
Enterobiasis, ascariasis, ankylostomiasis.
Hypersensitivity to any components of the drug.
Interaction with other medicinal products and other forms of interactions.
Do not use with piperazine, which is an antagonist of anthelmintic action of pyrantel.
In case of hepatic failure it is recommended to reduce the dose.
Enterobiasis: to prevent recontamination, strict hygienic measures should be taken: the perianal area should be cleaned daily; the fingernails should be cleaned several times a day. Children’s fingernails should be cut short. The underwear and pyjamas should be changed regularly. Prevent scratching. It is recommended to treat the whole family simultaneously, because the infection is often asymptomatic.
Usage during pregnancy and lactation.
Due to the absence of teratogenic effect of pyrantel in animals, congenital malformations in humans are not expected. Currently, congenital malformations or fetotoxic effects of pyrantel have not been clinically confirmed. However, monitoring of use of pyrantel during pregnancy is insufficient to exclude all the possible risks. Thus, this drug may be used during pregnancy only if absolutely necessary, after careful evaluation of the ratio benefit for a women/risk to a fetus, which is determined by the physician.
Due to the absence of published studies about the undesirable effect of pyrantel on children who are breastfed, and given the very low absorption of pyrantel, the use of the drug is possible, if necessary, after consulting the physician.
Effects on ability to drive and operate machinery.
Adverse reactions of the nervous system which may be rarely observed when using pyrantel, may affect the reaction rate when driving and the ability to work with other machinery.
Administration and dosage.
The drug may be taken at any time, there is no need to abstain from food and take purgative agents before taking the drug.
Enterobiasis and ascariasis.
When treating enterobiasis and ascariasis, the dosage usually is 10 mg/kg to 12 mg/kg given in single dose.
Children from 6 years: 1 tablet per 20 kg of body weight as single dose.
Adults with body weight less than 75 kg: 3 tablets as single dose.
Adults with body weight more than 75 kg: 4 tablets as single dose.
In case of enterobiasis, to fully get rid of parasites, strict hygienic measures should be taken, and the whole family should be treated simultaneously. To avoid repeated autoinfection it is recommended to take repeated dose 3 weeks after the first intake.
In endemic areas in case of contamination with Necator americanus or massive invasion of Ancylostoma duodenale the dosage is 20 mg/kg per day (taken in 1 or 2 doses) during 2-3 days.
Children from 6 years: 1 tablet per 10 kg of body weight per day.
Adults with body weight less than 75 kg: 6 tablets per day.
Adults with body weight more than 75 kg: 8 tablets per day.
In case of mild infestation with Ancylostoma duodenale (which usually occurs in non-endemic areas), it may be enough to take 10 mg/kg as single dose.
The drug should be prescribed in children older than 6 years. It is advisable to use the drug in the form of suspension in children under 6 years.
Due to the low coefficient of absorption, plasma drug concentrations are low. Overdose causes some gastrointestinal disorders (such as nausea, vomiting, diarrhea) and minor temporary disorders of the central nervous system (such as asthenia, dizziness, headache). Sometimes overdose increases the level of liver transaminases (AST). Specific antidotes are unknown. Immediate gastric lavage is recommended, as well as monitoring of functions of the respiratory and cardiovascular systems. The treatment is symptomatic.