How have poison control call volumes and hospitalization rates changed during periods of ivermectin misuse?
Executive summary
Poison control centers and emergency departments reported marked increases in ivermectin exposure calls and associated emergency visits during waves of misuse in 2021, with multiple public-health advisories documenting a rapid rise in calls and hospital encounters [1] [2]. Hospitalizations and intensive-care admissions were uncommon relative to total exposures but clearly rose in sentinel centers and in pharmacovigilance reports, and several severe outcomes including deaths were recorded in international databases [3] [4].
1. The surge in poison‑center calls: clear and abrupt
Multiple state and federal advisories documented a rapid uptick in calls to poison control centers after ivermectin was promoted for COVID-19, with the CDC and state health departments warning of increased human exposures and overdoses in 2021 compared with pre‑pandemic baselines [1] [5]. Surveillance snapshots show dramatic local spikes — the Oregon Poison Center went from roughly 0.25 calls per month in 2020 to 21 calls in August 2021, and national reporting captured a 245% jump in reported exposure cases from July to August 2021 in some datasets [3] [6]. Aggregated summaries and state notices also described threefold increases in poison‑center calls in the period of heightened misuse, and some states reported that a majority of recent calls involved veterinary formulations or products bought at livestock supply stores [2] [7] [8].
2. Hospitalizations: increased but concentrated and heterogeneous
Centers reporting large relative rises in calls also reported more emergency‑department visits and hospital admissions linked to ivermectin, though the absolute numbers in many series remained modest; for example, in the Oregon cluster six of 21 reported exposures led to hospitalization and four required intensive‑care treatment, with no deaths in that series [3]. CDC summaries and clinical reporting described examples of prolonged hospital stays and severe neurologic or cardiopulmonary presentations after ingestion of veterinary formulations or high doses, and national advisories warned clinicians of an increased frequency of adverse effects prompting ED and inpatient care [9] [1]. International pharmacovigilance reviews found serious ivermectin‑related reports including overdoses, neurologic disorders, hospitalizations and a small number of deaths in aggregated databases, highlighting that while uncommon, severe outcomes did occur [4].
3. Patterns of exposure — veterinary products, prescriptions, and timing
Analyses and public notices attributed much of the rise to people ingesting veterinary ivermectin or taking supratherapeutic doses in attempts to prevent or treat COVID‑19, with retail and mail‑order dispensing and veterinary supply use increasing during the relevant period [1] [8]. Some surveillance work showed an increase in prescriptions for human ivermectin as well — one report noted human prescriptions being many times higher than pre‑pandemic levels and a rapid month‑to‑month jump in mid‑2021 — but the sharpest increases in poison‑center calls were temporally tied to media circulation of ivermectin as a COVID‑19 remedy beginning in late 2020 and into 2021 [3] [10].
4. Limitations in the signal: what the data can — and cannot — show
The main surveillance inputs are poison‑center call counts, single‑center case series, and pharmacovigilance reports, which reliably show temporal increases in exposures and some severe cases but do not capture all exposures, direct causality, or complete hospitalization denominators; poison‑center data reflect reporting behavior and call‑seeking, not necessarily total community incidence [10] [3]. National aggregate counts reported in media and advisories (for example, reported increases between months or years) are consistent across multiple sources, but precise national hospitalization rates attributable to ivermectin misuse are not provided in the cited materials and likely vary by jurisdiction and health‑care seeking patterns [6] [1].
5. Why this matters: public health and misinformation dynamics
The convergence of elevated prescriptions, availability of concentrated veterinary formulations, and misinformation about COVID‑19 benefits produced a measurable increase in poison‑center calls and a nontrivial number of hospitalizations and severe events, prompting formal CDC and state warnings to clinicians and the public [1] [2]. Scientific reviews and clinical authorities uniformly note that randomized trials do not support ivermectin for COVID‑19 and advise against its use for that indication, which frames the spike in toxic exposures as preventable harm linked to off‑label use and misinformation [3] [11].