"Pinworms cause no harm or discomfort apart from anal itching, and treatment cures most cases. The key is to break the six-week cycle of pinworm reinfestation by killing any live pinworms and preventing the ingestion of eggs. A diagnosis should be confirmed before treating with medications."
"Medications kill only the adult worms and have no effect on developing eggs and larvae. The prescription of choice is mebendazole* and the nonprescription medication of choice is pyrantel. Other nonprescription medications that are available to treat pinworms include piperazine and pyrvinium. Both mebendazole and pyrantel are given as a single dose and repeated in two weeks to kill any newly ingested eggs. Since the eggs can be easily spread, everyone in the household must be treated with the medication. Reinfection is still common because live eggs continue to be excreted in feces for up to a week after the treatment."