What are the risks and side effects of taking ivermectin at incorrect doses?
Executive summary
High or incorrect doses of ivermectin can cause nausea, vomiting, diarrhea, low blood pressure, allergic reactions, dizziness, balance problems, seizures, coma and death — risks explicitly listed by the U.S. Food and Drug Administration (FDA) [1] and summarized by other outlets [2] [3]. Medical sources emphasize that ivermectin is safe only at approved doses for specific parasitic infections and warn against using veterinary formulations or taking it for unproven uses such as COVID-19 or cancer [3] [1] [4].
1. A drug with narrow, approved uses — and real consequences when misused
Ivermectin is an approved antiparasitic for specific human conditions at weight‑based doses; doctors say it is generally safe when prescribed and taken correctly, but regulatory agencies and clinicians have repeatedly warned that misuse—especially taking veterinary products or very high doses—can cause serious harm [3] [1] [2].
2. Overdose symptoms range from gastrointestinal upset to death
The FDA lists a clear spectrum of overdose signs: nausea, vomiting, diarrhea, hypotension (low blood pressure), allergic reactions (itching, hives), dizziness, ataxia (balance problems), seizures, coma and even death [1]. The New York Times likewise reports that the FDA has warned high doses can lead to coma or death [2]. Drugs.com documents adverse effects and cautions about overdoses from non‑human formulations [3].
3. Veterinary formulations amplify the danger
Multiple fact‑checks and health agencies note calls to poison centers when people ingested ivermectin formulations intended for animals; those products are highly concentrated and “may result in overdoses when used by humans,” so authorities advise never to consume animal products [3] [4]. The FDA message is consistent: fill prescriptions through legitimate pharmacies and avoid animal products [1].
4. Misuse peaked during the pandemic — and reporting shows real harm
Prescribing and nonprescription use of ivermectin surged early in the COVID‑19 pandemic despite evidence it does not prevent or treat COVID‑19; UCLA research found outpatient prescriptions rose several‑fold above pre‑pandemic levels, concentrated in some regions and populations [5]. Health agencies and the media linked that surge to increased poison‑center calls and safety warnings [4] [2].
5. Scientific debate exists about investigational uses, but safety data are limited
Some researchers and advocates have explored ivermectin in settings such as cancer and COVID‑19, and earlier meta‑analyses and trials produced conflicting results [6] [7]. However, mainstream regulators and clinicians state the drug has not been proven effective for COVID‑19 and caution against off‑label routine or long‑term use because the risks of repeated or high dosing are not well understood [2] [1] [6].
6. Public policy and access changes raise new safety questions
Several U.S. states have moved to expand over‑the‑counter access to ivermectin, a shift that proponents frame as improving access while public‑health experts warn it could increase self‑medication and related harms [8]. Red River Radio reports Texas joining other states in easing OTC availability; that policy change prompted experts to reiterate concerns about safety, misinformation and self‑medication risks [8].
7. How clinicians and agencies frame the tradeoffs
Regulators allow medically supervised off‑label prescribing but stress clinicians should weigh benefits against documented harms; the FDA and national health agencies explicitly decline approval for COVID‑19 use while warning that, “if there’s no benefit, then you only have risk,” a point echoed by clinicians quoted in the press [1] [2]. Fact‑checkers note ongoing misinformation campaigns that overstate benefits and downplay documented risks [4].
8. Practical takeaway and limits of current reporting
If taken at incorrect doses — especially veterinary formulations or very high repeated doses — ivermectin can cause serious, sometimes fatal, outcomes including seizures, coma and death [1] [2] [3]. Available sources do not mention specific dose thresholds for every adverse outcome in non‑clinical settings; they describe symptom lists and regulatory warnings rather than a precise mg/kg overdose chart [1] [3] [2]. For individual dosing and safety decisions, the reporting and guidance recommend consulting a licensed clinician and avoiding animal products [1] [3].
Limitations: my account is limited to the provided reporting and public‑health summaries; clinical dosing guidance and toxicology thresholds require authoritative prescribing information or toxicology reports not included in these sources [3] [1].