Nurses Compass
Drug Guide
Ivermectin
Classification
Therapeutic: Antiparasitic
Pharmacological: Endectocide, Antihelminthic
FDA Approved Indications
- Onchocerciasis (river blindness)
- Strongyloidiasis
- Pediculosis (lice infestation)
- Rosacea (Soolantra)
Mechanism of Action
Ivermectin binds to glutamate-gated chloride channels in nerve and muscle cells of parasites, causing increased permeability to chloride ions, hyperpolarization of the nerve or muscle cell, and eventual paralysis and death of the parasite.
Dosage and Administration
Adult: For onchocerciasis: 150 mcg/kg as a single dose, may be repeated after 3-12 months; for rosacea (Soolantra): 1 dose applied topically once daily for 8 weeks.
Pediatric: Dosing based on weight for parasitic infections; for lice in children, 5% topical formulation applied to affected area once or twice.
Geriatric: No specific dosage adjustment, but caution advised due to potential comorbidities and concomitant medications.
Renal Impairment: No specific dose adjustment recommendation; caution advised.
Hepatic Impairment: No specific dose adjustment; limited data.
Pharmacokinetics
Absorption: Orally well absorbed, especially on an empty stomach.
Distribution: Widely distributed in body fluids and tissues, crosses blood-brain barrier to a limited extent.
Metabolism: Metabolized in the liver, primarily via CYP3A4 enzyme.
Excretion: Excreted mainly in feces; small amount in urine.
Half Life: Approximately 12-16 hours.
Contraindications
- hypersensitivity to ivermectin or components
Precautions
- Caution in individuals with compromised blood-brain barrier, or with concomitant medications that may affect CNS or hepatic function. Use in pregnancy and lactation only if clearly needed.
Adverse Reactions - Common
- Mild skin rash (Common)
- Dizziness (Common)
- Gastrointestinal upset (nausea, diarrhea) (Common)
Adverse Reactions - Serious
- Neurotoxicity (ataxia, confusion, mydriasis) (Rare)
- Severe hypersensitivity reactions (Rare)
Drug-Drug Interactions
- CYP3A4 inhibitors (e.g., azoles, macrolides) may increase ivermectin levels
Drug-Food Interactions
N/ADrug-Herb Interactions
N/ANursing Implications
Assessment: Assess for parasitic infections, neurological symptoms, and hypersensitivity.
Diagnoses:
- Risk for neurological impairment due to neurotoxicity
- Risk for hypersensitivity reactions
Implementation: Administer as prescribed; monitor for adverse effects, especially neurotoxicity.
Evaluation: Evaluate treatment efficacy and monitor for adverse reactions.
Patient/Family Teaching
- Take medication exactly as prescribed.
- Report any neurological symptoms such as dizziness, confusion.
- Avoid driving or operating machinery if experiencing dizziness.
- Maintain good hygiene to prevent reinfestation.
- Use topical formulations as directed, do not exceed recommended frequency.
Special Considerations
Black Box Warnings:
- Potential for neurotoxicity, especially in individuals with blood-brain barrier compromise or high parasite burdens.
Genetic Factors: Variations in CYP3A4 activity may affect drug metabolism.
Lab Test Interference: No significant impact reported.
Overdose Management
Signs/Symptoms: Neurological symptoms such as dizziness, ataxia, confusion.
Treatment: Supportive care; no specific antidote. Induce vomiting or administer activated charcoal if ingestion is recent.
Storage and Handling
Storage: Store at room temperature, 20°C to 25°C (68°F to 77°F).
Stability: Stable under recommended conditions.