What are the FDA‑approved indications and standard human dosages for ivermectin?

1. What the FDA has approved: indication-by-indication snapshot

The oral formulation of ivermectin (marketed as Stromectol) is FDA‑approved to treat intestinal strongyloidiasis and onchocerciasis (river blindness), while topical ivermectin formulations have FDA approval for dermatologic uses including a 0.5% lotion (Sklice) for head lice and topical ivermectin products approved for inflammatory lesions of rosacea in adults; these approvals and product distinctions are explicitly noted in FDA and clinical drug references ^{[1] [2] [3]}.

2. Standard human dosages — oral (weight‑based) and how they are used

Clinical dosing for oral ivermectin is weight‑based and typically given as a single oral dose for many parasitic indications; standard regimens used in practice and reflected in prescribing resources recommend approximately 150–200 micrograms per kilogram (mcg/kg) as a single dose for infections such as strongyloidiasis, with retreatment schedules or repeated dosing for onchocerciasis as determined by specialists and public‑health programs ^{[7] [1]}. Detailed, indication‑specific dosing, monitoring and retreatment intervals are available in drug monographs and dosing guides that summarize FDA labeling and clinical practice ^{[7] [8]}.

3. Standard human dosages — topical products and application rules

Topical ivermectin preparations follow product‑specific instructions: for head lice, the FDA‑approved 0.5% lotion (Sklice) is a single‑use topical treatment for patients six months and older, whereas topical ivermectin creams for rosacea are applied according to the product label (typically once daily) and are distinct from oral dosing both in concentration and safety profile ^{[2] [3]}.

4. What ivermectin is not approved for, and the evidence controversies

Regulators have been unequivocal that ivermectin is not authorized or approved for prevention or treatment of COVID‑19 in humans or animals, and the FDA and CDC have warned of hospitalizations after people self‑medicated with animal formulations or used unapproved doses; laboratory studies showing antiviral effects in vitro do not translate into established safe, effective human COVID‑19 regimens and would require doses far above approved limits to reproduce in‑vitro concentrations, raising toxicity concerns ^{[4] [9] [6]}.

5. Safety limits, misuse risks, and off‑label practice

While ivermectin has a long history as an antiparasitic with a generally tolerable safety profile when used at approved human doses, regulators and clinical guides caution that veterinary products contain different formulations and concentrations that can be toxic to people, overdose symptoms can be severe, and some off‑label uses (including for scabies or other parasitic or dermatologic conditions) should be managed by clinicians with monitoring for interactions and adverse reactions ^{[4] [6] [7]}.

6. Competing narratives and why clarity matters

Public interest in repurposing ivermectin—driven by an in‑vitro antiviral study and by social media and political currents—created confusion and shortages, prompting agencies and clinical societies to reiterate that approved indications and dosages remain the standard of care, that off‑label prescribing should be evidence‑based, and that misuse of veterinary formulations endangers patients; the literature also records ongoing research into other potential therapeutic roles, but such research has not changed the FDA‑approved indications or standard dosing guidance to date ^{[9] [6] [10]}.