At a glance
- The preferred medication to treat baylisascariasis is albendazole.
- If albendazole is not immediately available, mebendazole or ivermectin may be used in the interim.
- Treatment should be initiated as soon as possible after ingestion of infectious material, ideally within three days.
Treatment options
In cases where suspicion of exposure is high, immediate treatment with albendazole (25 – 50 mg/kg per day by mouth for 10 – 20 days) may be appropriate. Treatment is successful when administered soon after exposure to abort the migration of larvae. Indications for immediate treatment may include known oral exposure to raccoon feces, presence of Baylisascaris eggs in the feces of the implicated animal or animals, and suspected oral exposure to raccoon feces in an area where the prevalence of raccoon infection is known to be high. Treatment should be initiated as soon as possible after ingestion of infectious material, ideally within three days. If albendazole is not immediately available, mebendazole or ivermectin may be used in the interim.
For clinical baylisascariasis, treatment with albendazole, at the dose given above, with concurrent corticosteroids to help reduce the inflammatory reaction is indicated to attempt to control the disease.
*Oral albendazole, oral mebendazole, and oral ivermectin are available for human use in the United States.
Care precautions
Treatment during pregnancy
Albendazole is a pregnancy category C drug. There are limited data on the use of albendazole in pregnant women. The available evidence suggests no difference in congenital abnormalities in the children of women accidentally treated with albendazole during mass drug administration (MDA) campaigns compared with those who were not. In MDA campaigns for which the World Health Organization (WHO) has determined that the benefits of treatment outweigh the risks, WHO allows use of albendazole in the 2nd and 3rd trimesters of pregnancy. However, healthcare providers should balance the risks of treatment for the fetus with the risks of disease progression in the woman in the absence of treatment.
Pregnancy Category C: Either studies in animals have revealed adverse effects on the fetus (teratogenic or embryocidal, or other) plus there are no controlled studies in women, or studies in women and animals are not available. Prescribe albendazole only if the potential benefits to the woman justify the potential risks to the fetus.
Treatment during lactation
Albendazole is minimally excreted in human milk. WHO has concluded that a single oral dose of albendazole can be given to lactating women.
Treatment in pediatric patients
The safety of albendazole in children less than 6 years old is not certain. Studies of the use of albendazole in children as young as one year old suggest that it is safe. According to WHO guidelines for MDA campaigns, children as young as one year of age (able to safely swallow tablets) can take albendazole. These campaigns have treated many children under six years old with albendazole, albeit at a reduced dose.
Treatment during pregnancy
Mebendazole is a pregnancy category C drug. Data on the use of mebendazole in pregnant women are limited. The available evidence suggests no difference in congenital anomalies in the children of women treated with mebendazole during mass drug administration (MDA) campaigns compared with those who were not. In MDA campaigns in countries where soil-transmitted helminths are common, World Health Organization (WHO) has determined that the benefits of treatment outweigh the risks and WHO allows use of mebendazole in the 2nd and 3rd trimesters of pregnancy. However, in a pregnant woman infected with a soil-transmitted helminth, balance the risks of treatment for the fetus with the risks of disease progression in the woman in the absence of treatment.
Pregnancy Category C: Either studies in animals have revealed adverse effects on the fetus (teratogenic or embryocidal, or other) plus there are no controlled studies in women, or studies in women and animals are not available. Prescribe mebendazole only if the potential benefits to the woman justify the potential risks to the fetus.
Treatment during lactation
Mebendazole is minimally excreted in breast milk. WHO classifies mebendazole as compatible with breastfeeding and allows its use in lactating women.
Treatment in pediatric patients
The safety of mebendazole in children is unclear. There are limited data in children under 2 years old. The WHO Model List of Essential Medicines for Children lists mebendazole as an intestinal antihelminthic medicine that can be used for children older than 2 years of age.
Treatment during pregnancy
Ivermectin is a pregnancy category C drug. Data on the use of ivermectin in pregnant women are limited, though the available evidence suggests no difference in congenital abnormalities in the children of women who were accidentally treated during mass drug administration (MDA) campaigns with ivermectin compared with those who were not. The World Health Organization (WHO) excludes pregnant women from MDA campaigns that use ivermectin. In a pregnant woman infected with a soil-transmitted helminth, balance the risks of treatment for the fetus with the risks of disease progression in the woman in the absence of treatment.
Pregnancy Category C: Either studies in animals have revealed adverse effects on the fetus (teratogenic or embryocidal, or other) plus there are no controlled studies in women, or studies in women and animals are not available. Prescribe ivermectin only if the potential benefits in the woman justify the potential risks to the fetus.
Treatment during lactation
Ivermectin is excreted in low concentrations in human milk. Treat breastfeeding women with ivermectin only when the risks of disease progression in the untreated mother outweigh the risks to the infant.
Treatment in pediatric patients
The safe use of ivermectin in children weighing less than 15 kg (33 lbs) is unclear. According to the WHO guidelines for MDA campaigns, ivermectin can safely treat children at least 90 cm (35 in) tall. The WHO growth standard curves show that 50% of boys reach this height by age 28 months and 50% of girls by age 30 months. Some MDA campaigns use ivermectin to treat