II. Indication

  1. Scabies (refractory to Permethrin 5%)
  2. Head Lice
  3. Strongyloidiasis
  4. Onchocerciasis

III. Mechanism

  1. Developed initially as veterinary anti-parasitic agent
  2. Related to Macrolide antibiotics
  3. Also decreases Nerve Impulse transmission
    1. Potentiates GABA-gated chloride channels

IV. Pharmacokinetics

  1. Peak Level: 3-6 hours after intake
  2. Half-Life: >12 hours
  3. Metabolized by Cyp 3A4
  4. Crosses blood brain barrier via P-Glycoprotein (ABCB1 Transporter)

V. Preparations

  1. Ivermectin 6 mg tablet

VI. Dosing

  1. Scabies or Head Lice
    1. Ivermectin 200 mcg/kg PO x1 dose, repeat in 10 days
  2. Strongyloidiasis
    1. Ivermectin 200 mcg/kg PO for 1 dose
  3. Onchocerciasis
    1. Ivermectin 150 mcg/kg PO for 1 dose

VII. Efficacy: Scabies

VIII. Precautions

  1. Safe in children >15 kg (33 pounds)
  2. Avoid in Lactation
  3. Pregnancy Category: C

IX. Adverse Effects: Reaction - Allergy to Parasite Death

X. Adverse Effects: Toxicity or Overdose

  1. Doses <500 mg in adults and <5mg/kg in children are typically without reaction
  2. In 2021, patients were taking very high doses for COVID-19 (based on little evidence of benefit)
    1. High dose toxicity (Seizures, coma, death) was at risk at these doses (e.g. 600 mg taken for several days)
    2. Patients ingested high risk formulations (topical Ivermectin, veterinary Ivermectin)
  3. Findings typically resolve within 6-8 hours of ingestion
  4. Gastrointestinal Findings
    1. Nausea or Vomiting
    2. Abdominal Pain
    3. Diarrhea
  5. Neurologic Findings
    1. Headache
    2. Dizziness
    3. Hallucinations
    4. Confusion
  6. Cardiopulmonary Findings
    1. Hypotension
    2. Tachycardia
  7. Skin Findings
    1. Urticaria
    2. Edema
  8. Management
    1. See Unknown Ingestion
    2. Activated Charcoal
      1. Indicated in early presentation of large ingestion
    3. Supportive Management
      1. ABC Management
      2. Benzodiazepines for Seizures
      3. Consider Intravenous Lipid Emulsion

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Related Studies

Cost: Medications

ivermectin (on 5/17/2017 at Medicaid.Gov Survey of pharmacy drug pricing)
IVERMECTIN 3 MG TABLET Generic $3.90 each

Ontology: Ivermectin (C0022322)

Definition (NCI) A macrocyclic lactone derived from Streptomyces avermitilis with antiparasitic activity. Ivermectin exerts its anthelmintic effect via activating glutamate-gated chloride channels expressed on nematode neurons and pharyngeal muscle cells. Distinct from the channel opening induced by endogenous glutamate transmitter, ivermectin-activated channels open very slowly but essentially irreversibly. As a result, neurons or muscle cells remain at either hyperpolarisation or depolarization state, thereby resulting in paralysis and death of the parasites. Ivermectin does not readily pass the mammal blood-brain barrier to the central nervous system where glutamate-gated chloride channels locate, hence the hosts are relatively resistant to the effects of this agent.
Definition (MSH) A mixture of mostly avermectin H2B1a (RN 71827-03-7) with some avermectin H2B1b (RN 70209-81-3), which are macrolides from STREPTOMYCES avermitilis. It binds glutamate-gated chloride channel to cause increased permeability and hyperpolarization of nerve and muscle cells. It also interacts with other CHLORIDE CHANNELS. It is a broad spectrum antiparasitic that is active against microfilariae of ONCHOCERCA VOLVULUS but not the adult form.
Concepts Pharmacologic Substance (T121) , Organic Chemical (T109)
MSH D007559
SnomedCT 387559003, 96138006
English Ivermectin, ivermectin, ivermectin (medication), IVERMECTIN, Ivermectin [Chemical/Ingredient], Avermectin A1a, 5-O-demethyl-25-de(1-methylpropyl)-22,23-dihydro-25-(1-methylethyl)-, Ivermectin (product), Ivermectin (substance)
Swedish Ivermektin
Czech ivermektin
Finnish Ivermektiini
Japanese イベルメクチン
Polish Iwermektyna, Ivermectin
Spanish ivermectina (producto), ivermectina (sustancia), ivermectina, Ivermectina
French Ivermectine
German Ivermectin
Italian Ivermectina
Portuguese Ivermectina

Ontology: Stromectol (C0723477)

Definition (MSH) Oral preparation of ivermectin.
Concepts Organic Chemical (T109) , Pharmacologic Substance (T121)
MSH D007559
English Stromectol, Ivermectin Merck Brand, Merck Brand of Ivermectin

Ontology: Mectizan (C0751253)

Concepts Organic Chemical (T109) , Pharmacologic Substance (T121)
MSH D007559
English Mectizan