What have poison control centers reported about trends in ivermectin exposures since 2020?
Executive summary
Poison control centers across the United States reported a clear rise in human ivermectin exposure calls beginning in late 2020 and accelerating in 2021, with national and state-level data showing multiple-fold increases compared with pre-pandemic baselines [1] [2]. Public-health agencies including the CDC and state poison centers linked these rises to attempts to self-treat or prevent COVID-19, often involving veterinary formulations or prescriptions dispensed at much higher rates than before the pandemic [1] [2].
1. Sharp increases in calls: what the numbers show
Multiple data sources documented large relative increases in ivermectin exposure reports to poison centers: the American Association of Poison Control Centers and the National Poison Data System recorded hundreds to thousands of exposure reports in 2021, representing a three-fold rise in January 2021 versus pre-pandemic baseline and spikes as high as five-fold in mid‑2021 [1] [3]; specific comparisons show U.S. calls rising from dozens in mid‑2020 to several hundred by August 2021, with one national bulletin citing 1,143 exposure reports from January through August 2021 [4] [2].
2. When and where the surges occurred
The temporal pattern links two waves: an early pandemic interest in antimalarials in spring 2020 produced spikes in hydroxychloroquine exposures, while claims about ivermectin published in late 2020 preceded a surge in ivermectin-related calls beginning January 2021 and peaking in summer/autumn 2021, with particularly large state-level jumps reported in Texas, Oregon and others [5] [6] [7]. CDC reporting and state health advisories documented a rapid rise in outpatient ivermectin dispensing—peaking at tens of thousands of prescriptions per week in January 2021 and again surging in July–August 2021—which paralleled the poison-center call increases [1] [8].
3. Nature of exposures and clinical consequences reported
Poison centers and case reports repeatedly singled out misuse of veterinary formulations and self-directed dosing as common threads: many calls involved people ingesting animal ivermectin products or human formulations obtained without clear medical supervision, leading to gastrointestinal symptoms, neurologic effects (dizziness, confusion, seizures), emergency‑department visits and some hospitalizations; the CDC and NEJM summarized cases of severe illness tied to such misuse [1] [9] [2]. Surveillance analyses and poison-center advisories warned that overdoses can produce hypotension, altered mental status and, rarely, life‑threatening neurologic events when combined with other CNS depressants [8] [9].
4. Data strengths and important caveats
The rise is robust across multiple reporting systems—state poison centers, NPDS aggregates and WHO pharmacovigilance reports—but the absolute counts are modest relative to population size and vary by source and timeframe (for example, Texas reported a 591% increase between 2020 and 2021 based on state network figures, while Oregon documented jumps from near‑zero monthly calls in 2020 to dozens in 2021) [6] [7]. Limitations noted in the literature include variable reporting practices across centers, exclusion of certain dispensing channels (mail order, veterinary prescriptions), and the fact that increased media attention and prescription volume can both drive higher reporting without directly quantifying incidence of severe poisonings [1] [10].
5. Drivers, competing narratives and implicit agendas
Researchers and public-health agencies point to misinformation—social media amplification of preliminary or in vitro ivermectin studies and promotion by some public figures—as a primary driver of self‑treatment and resulting exposures, a perspective echoed in poison‑center warnings and news accounts [5] [11] [2]. Alternative explanations are limited in the public record: some increases reflect legitimately prescribed human ivermectin (prescriptions rose dramatically at times), but surveillance notes stress that a substantial share of harmful exposures involved veterinary products or unsupervised use rather than physician‑directed therapy [1] [3].
6. What's settled, what's open and the public‑health takeaway
What is well documented is a temporal association between public discussion of ivermectin for COVID‑19 and higher rates of poison‑center reports and adverse‑event notifications in 2020–2021; what remains less precise is the full clinical burden (how many exposures led to long‑term harm) and the degree to which prescribing versus nonprescription use contributed to outcomes because of data gaps and reporting variability [12] [10]. Until better, harmonized surveillance is available, the consistent recommendation from poison centers and the CDC is that ivermectin should be used only as prescribed for approved indications and that health professionals counsel patients against self‑treatment with veterinary products [1] [13].