Ivermectin Dosing for Parasitic Infections

Standard Dosing Recommendation

The standard dose of ivermectin for parasitic infections in adults is 200 mcg/kg (0.2 mg/kg) as a single oral dose taken on an empty stomach with water 1

For strongyloidiasis, a single dose of 200 mcg/kg orally is recommended, with extended dosing for immunocompromised patients: 200 mcg/kg on days 1, 2, 15, and 16 1
For scabies, 200 mcg/kg orally, repeated in 2 weeks, is recommended, with the second dose necessary due to ivermectin's limited ovicidal activity 2
For pediculosis (lice), a single dose of 200 or 400 mcg/kg orally is recommended for lice resistant to topical agents, with a second dose given after 9-10 days 3
For loiasis, 150-200 mcg/kg as a single dose or repeated at monthly, quarterly, or biannual intervals is recommended, depending on microfilarial load, with a critical safety warning to exclude co-existing onchocerciasis before treating loiasis 1
For lymphatic filariasis, 200 mcg/kg combined with doxycycline 200 mg daily for 6 weeks is recommended for optimal adult worm killing 1

Ivermectin should be taken on an empty stomach with water for strongyloidiasis and onchocerciasis, but with food for scabies to increase bioavailability and epidermal penetration 1, 2

No dose adjustments are required for patients with renal impairment 1
The safety of multiple doses in patients with severe liver disease is not established 1
Ivermectin is classified as "human data suggest low risk" in pregnancy and is probably compatible with breastfeeding, but permethrin or pyrethrins with piperonyl butoxide are preferred alternatives for pregnant and lactating women 1, 2
Children under 10 years should not receive ivermectin for scabies; permethrin cream is preferred 1, 2

Always exclude Loa loa infection before treating with ivermectin in anyone who has traveled to endemic regions, due to the risk of severe adverse events including encephalitis in hypermicrofilaremic patients (>8,000 mf/mL) with loiasis 1, 4
Exercise particular caution in frail elderly patients, as one study demonstrated increased mortality among elderly, debilitated persons who received ivermectin 1

For travelers with eosinophilia and negative stool studies, consider empirical treatment with albendazole 400 mg plus ivermectin 200 mcg/kg as a single dose to cover prepatent or undetected geohelminth infections 1