Unfortunately, sites on the internet are recommending Ivermectin for treatment of COVID. Co-ops are running out of the drug as people are buying it for human consumption. Poison Centers throughout the US are answering increasing number of calls about exposure/OD of Ivermectin.
The following are the clinical guidelines developed by the toxicologists in the poison center to address this exposure.
Background: Ivermectin is a semisynthetic anti-parasitic drug that is used to treat intestinal strongyloidiasis and onchocerciasis in humans. It has been misused to treat COVID-19 without FDA/CDC approval/recommendation.
Topical forms can be used for head lice and skin diseases (rosacea).
Mechanism of Toxicity:
Ivermectin is a semisynthetic anti parasitic drug. Death of the parasite is caused by hyper polarization of cells leading to paralysis through glutamate gated chloride ion channels. It also may act as an agonist of GABA and interfering GABA mediated CNS synaptic transmission - this may explain the cause of the altered mental status. Furthermore, toxic effects may be increased when combined with other gabanergic agents such as barbiturates, benzodiazepines, and valproic acid.
Toxic Dose: not well established, In a 15 kg child, 6.6 to 8.7 mg/kg caused vomiting, somnolence, and mild cardiovascular effects. An estimated dose of 13.9 mg/kg in a 7 month old child produced vomiting. 1 gram has resulted in serious toxicity.
Therapeutic Dose: 150 mcg/kg to 200 mcg/kg for peds/adults > 15 kg as a one time dose or for river blindness, can be repeated every 3-12 months.
Observation time: 6 hours and if asymptomatic, can be discharged with return precautions, otherwise admit till asymptomatic and laboratory abnormalities if present, normalize.
Unapproved dosing for COVID-19 (clinical trial data): 0.3-0.4 mg/kg/day for 5 days
Presentation: Nausea, vomiting, diarrhea, altered mental status, hypotension, allergic reactions, ataxia, seizures, coma, and death. Liver injury/failure has been reported (case report). In addition, neutropenia has been reported in a related agent.
- GI decontamination: none recommended
- Labs: Recommend to check CMP and CBC (a related agent can cause neutropenia). Electrolyte and renal abnormalities could occur from nausea/vomiting/diarrhea.
- Mainstay of treatment is supportive care
- In animal studies, intralipid emulsion therapy has been used to treat Ivermectin Toxicity. A review article by Gosselin et al in Clin Tox has a neutral recommendation in both life threatening and non-life threatening toxicity. If patient is experiencing severe toxicity, please discuss with Toxicologist on call prior to recommending intralipid emulsion therapy. In patients with concurrent COVID-19 disease, lipids should not be administered due to concerns of lung injury.
- Enhanced elimination: None recommended given high protein binding and large volume of distribution but serious toxicities will be evaluated on a case by case basis.
This question was prepared by Rebecca Bruccoleri MD Medical Director TPC
I thought this topic was important enough to warrant a second Question of the Week. I have attached an infographic that you may want to print and display in offices/EDs etc. The infographic was developed by Shelby Bennett, Pharm D and Masters of Management in Healthcare Candidate; Lipscomb University College of Pharmacy.
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Donna Seger, MD
Tennessee Poison Center www.tnpoisoncenter.org
Poison Help Hotline: 1-800-222-1222