Ascaris - Treatment

Treatment

Infections with A.lumbricoides are easily treated with a number of single dose anthelmintic drugs, which ensures compliance:

• pyrantel pamoate or embonate given as a single oral dose of 10 mg/kg body weight;
• levamisole given as a single oral dose of 2.5 mg/kg body weight;
• mebendazole given as a single oral dose of 500 mg for all individuals older than 1 years or 100 mg twice daily for 3 days;
• albendazole given as a single oral dose of 400 mg for all individuals older than 2 year and 200 mg for a child aged 12 - 24 months.

The drugs levamisole and pyrantel and its derivatives act by paralysing worms so that they are expelled from the gut by the normal action of peristalsis. The benzimidazole drugs albendazole and mebendazole interfere with the assembly of microtubules in mitochondria and block the uptake of glucose so that the worms are killed and pass out of the gut in the stools. Neither albendazole nor mebendazole are well absorbed from the gut, but any absorbed drug is rapidly metabolised in the liver and is excreted in the urine.

The World Health Organization recommends mass treatment of all children once a year in areas where more than 20% of children are infected and mass treatment twice a year where more than 50% of children are infected. The cost-effectiveness of the lower threshold has been questioned.

Many parasitic disease specialists are seeing increased incidence and recurrence of roundworm in the U.S. and are thereby increasingly recommending follow up courses of medication to treat internal eggs which have not yet hatched, in addition to the initial treatment period as above. This consists of sporadic treatment with albendazole or similar for a period of three days each month for up to five months after the initial treatment period.

When worms are present in large numbers they may block the intestine or the bile or pancreatic ducts, which may require surgery to remove the worms.