What is the recommended dose of ivermectin (antiparasitic medication) for an 80kg man?

Ivermectin Dosage for an 80kg Man

For an 80kg man, the recommended dose of ivermectin is 16mg (calculated at 200 μg/kg) as a single oral dose. 1

Dosage Calculation

The FDA-approved dosing for ivermectin is weight-based at 200 μg/kg (micrograms per kilogram) for treatment of parasitic infections such as strongyloidiasis 1. For an 80kg individual, this calculates to:

• 80kg × 200 μg/kg = 16,000 μg = 16mg

Administration Guidelines

• Ivermectin should be taken as tablets on an empty stomach with water 1
• If using standard 3mg tablets, this would require approximately 5-6 tablets (rounded to nearest whole tablet)
• According to the FDA dosage guidelines table for strongyloidiasis, patients ≥80kg should receive a dose calculated at 200 μg/kg 1

Specific Parasitic Conditions

Different parasitic conditions may require different dosing regimens:

1. Strongyloidiasis: Single oral dose of 200 μg/kg (16mg for 80kg) 1
2. Onchocerciasis: Single oral dose of 150 μg/kg (12mg for 80kg) 1
3. Scabies:
   • Standard: Single oral dose of 200 μg/kg 2
   • Crusted/severe: Multiple doses on days 1,2,8,9, and 15 2
4. Whipworm (Trichuris trichiura): 200 μg/kg once daily for 3 days in combination with mebendazole 2

Follow-up and Monitoring

• For strongyloidiasis, follow-up stool examinations should be performed to verify eradication of infection 1
• For scabies, re-evaluation should be performed after 1 week if symptoms persist 2
• For certain parasitic infections, retreatment may be necessary if clinical response is inadequate

Important Considerations

• Bioavailability of ivermectin is increased when taken with food 3, though the FDA label recommends taking it on an empty stomach 1
• The effect of a high-fat breakfast compared to fasted administration appears minimal according to recent research 3
• No dosage adjustment is required for patients with renal impairment 4
• Caution is advised in patients with severe liver disease as the safety of multiple doses is not well established 2

Potential Side Effects

Ivermectin is generally well-tolerated with few adverse effects. Side effects, when they occur, are typically mild and transient, resolving within the first five days of treatment 5.

Clinical Pearls

• For parasitic infections requiring repeat dosing, the timing between doses is important for efficacy
• Double-dose ivermectin (two doses given two weeks apart) may be more effective than a single dose in patients with concomitant illnesses 6
• Complete resolution of skin lesions typically occurs within 7-14 days for conditions like scabies 4

Following these guidelines will ensure appropriate dosing of ivermectin for an 80kg man while maximizing efficacy and minimizing potential adverse effects.