What are the approved human uses and dosages of ivermectin in the United States (year 2025)?
Executive summary
Ivermectin is an FDA‑approved antiparasitic medicine in the United States for specific human parasitic infections and certain topical dermatologic uses; the common oral human dosing is weight‑based, typically 200 micrograms per kilogram given as a single dose for approved systemic indications (Mayo Clinic) [1]. The drug is not approved by the FDA to prevent or treat COVID-19 or to treat cancer, and higher, non‑approved dosing has known toxicity risks and prompted repeated public health warnings (SCDHEC; New York Times; Wikipedia) [2] [3] [4].
1. What the FDA has approved: antiparasitic and dermatologic indications
Ivermectin’s established, approved human indications in the U.S. are antiparasitic: treatment of onchocerciasis (river blindness), strongyloidiasis (threadworm) and other worm infections, and there are separate topical formulations that have regulatory approval for conditions such as head lice and rosacea (news coverage and regulatory summaries note the antiparasitic approvals dating back to the 1990s and topical approvals) [5] [6] [4].
2. Approved oral dosing regimen for systemic parasitic infections
For oral use in adults and children weighing 15 kg or more, clinical guidance lists dosing based on body weight with the usual regimen being 200 micrograms (mcg) per kilogram of body weight given as a single dose for the approved systemic parasitic infections; tablets are commonly available in 3 mg strengths and the precise dose must be determined by a clinician (Mayo Clinic) [1].
3. What is not approved and persistent misinformation
Federal regulators and major public‑health bodies have explicitly not approved ivermectin for COVID‑19 treatment or prevention, and authorities repeatedly warned against such use after a surge in off‑label prescribing and poison‑control reports during the pandemic (South Carolina DHEC; WHO/FDA cited in reporting) [2] [7] [3]. Reporting documents that large clinical trials failed to show consistent benefit for COVID‑19 and that some early supportive studies were later retracted for data problems, fueling both misuse and misinformation (Courage Against Cancer; New York Times) [7] [3].
4. Safety, toxicity and dosing limits versus claims
Reputable pharmacologic summaries emphasize that the inhibitory concentrations seen in cell studies against SARS‑CoV‑2 would require oral doses many times higher than FDA‑approved regimens—estimates cited are roughly 35 times the maximum approved dose—levels associated with ivermectin poisoning and central nervous system effects; overdose presentations reported include nausea, confusion, visual disturbances, seizures and, in extreme cases, death (Wikipedia; reporting on toxicity and CDC warnings) [4].
5. Political and market pressures shaping access, not medical consensus
Since 2024–2025, several state legislatures moved to ease over‑the‑counter access or otherwise expand availability, and conservative political actors have promoted broader access despite FDA warnings; these policy moves reflect political and constituent pressures rather than new clinical evidence of benefit for non‑approved uses, and reporting warns that some policy advocacy aims to circumvent federal regulatory conclusions (Texas Tribune; New York Times; NPR‑affiliated reporting) [6] [3] [8].
6. Research landscape and legitimate investigational uses
Academic interest persists in repurposing ivermectin for other diseases, with preclinical work and internet search spikes noted through 2025, but systematic reviews and surveillance of trials show no reliable human clinical evidence supporting use in COVID‑19 or cancer as of the cited reporting; ongoing investigational activity does not equate to approval and has not established safe, effective alternative dosing regimens (Annals of Oncology summary; Naunyn‑Schmiedeberg review; New York Times) [9] [10] [3].
7. Bottom line for licensed clinical practice
In licensed clinical practice in the United States in 2025, ivermectin is approved for specific parasitic infections with a standard oral dose of about 200 mcg/kg as a single dose for systemic indications and for certain topical dermatologic conditions; it is not FDA‑approved for COVID‑19 or cancer, and higher or repeated dosing outside approved indications carries recognized toxicity risks and lacks regulatory endorsement (Mayo Clinic; SCDHEC; Wikipedia; mainstream reporting) [1] [2] [4] [3].