Ascaris lumbricoides is a parasitic roundworm, or nematode, that can infect the small bowel. Ascariasis is the most common human worm infection worldwide, reports the Centers for Disease Control and Prevention. Among the U.S. population, ascariasis is uncommon. Infections can occur, however, during travel to areas of the world with a high prevalence of ascariasis, including sub-Saharan Africa, east Asia, China and parts of Central and South America. Oral anti-parasitic medications are the primary treatment for Ascaris lumbricoides infections.
Albendazole
Albendazole is an anti-parasitic drug with activity against Ascaris lumbricoides and a variety of other human worms. The drug interferes with the absorption of sugar by the worms, leading to starvation and death of the parasites. For the treatment of ascariasis, the manufacturer recommends a single 400 mg dose taken with food. The dose is the same for children and adults, although the World Health Organization recommends not using the drug in children younger than 1 year of age. Possible side effects include headache, nausea, vomiting and abdominal pain.
In an April 2008 review article published in the "Journal of the American Medical Association," Jennifer Keiser, Ph.D., and Jürg Utzinger, Ph.D., report a cure rate of 88 percent with single-dose albendazole for ascariasis.
Mebendazole
Mebendazole is chemically similar to albendazole, with the same mechanism of action against Ascaris lumbricoides. Mebendazole also has activity against a variety of other human worms. The manufacturer's recommended dosage of mebendazole for the treatment of ascariasis is 100 mg orally with food in the morning and evening for three days. The dose is the same for children and adults, although the prescribing information urges consideration of the risks and benefits in administering the drug to a child younger than age 2. Mebendazole side effects are similar to those associated with albendazole. The recommended treatment regimen results in a 98 percent cure rate for ascariasis, according to the FDA-approved prescribing information for the drug.
In developing countries, a single 500 mg oral dose of mebendazole is commonly used for the treatment for ascariasis. Keiser and Utzinger report that this treatment regimen cures ascariasis in approximately 95 percent of cases.
Pyrantel
Pyrantel is another option for treating an Ascaris lumbricoides infection. The drug paralyzes the worms, leaving them unable to cling to the intestinal wall. The free-floating, paralyzed worms pass from the body in the stool. The recommended dose of pyrantel for the treatment of ascariasis is a single dose of 10 mg per kg of body weight administered with or without food. Possible side effects include abdominal cramps, diarrhea, nausea, vomiting, decreased appetite and headache. Keiser and Utzinger report an 88 percent cure rate with single-dose pyrantel for the treatment of Ascaris lumbricoides infection.
References
- Centers for Disease Control and Prevention: Ascaris Fact Sheet
- World Health Organization: Soil-transmitted Helminths
- Drugs.com: Albendazole
- World Health Organization: Albendazole Administration Poster
- "Journal of the American Medical Association"; Efficacy of Current Drugs Against Soil-Transmitted Helminth Infections, Systematic Review and Meta-analysis; Jennifer Keiser, Ph.D., Jürg Utzinger, Ph.D.; April 2008
