What is the appropriate ivermectin dose for a 48‑kilogram adult male?

Ivermectin Dosing for 48 kg Adult Male

For a 48 kg adult male, administer 3 tablets of ivermectin 3 mg (total 9 mg) as a single oral dose on an empty stomach with water. 1

Indication-Specific Dosing

The appropriate ivermectin dose depends on the specific parasitic infection being treated:

Strongyloidiasis

• Dose: 200 mcg/kg as a single oral dose 1
• For 48 kg patient: 9.6 mg (approximately 3 tablets of 3 mg each)
• According to FDA dosing guidelines, patients weighing 36-50 kg receive 3 tablets 1
• Take on empty stomach with water to optimize absorption 1
• Follow-up stool examinations should verify eradication; additional doses generally not necessary 1

Onchocerciasis

• Dose: 150 mcg/kg as a single oral dose 1
• For 48 kg patient: 7.2 mg (approximately 2-3 tablets)
• FDA guidelines specify patients 45-64 kg receive 3 tablets 1
• Retreatment may be considered at intervals as short as 3 months for individual patients 1
• In mass distribution campaigns, 12-month intervals are most common 1

Loiasis (Alternative Treatment)

• Dose range: 150-200 mcg/kg 2
• Most commonly given as single dose, though some guidelines recommend daily dosing for up to 10 days in endemic settings 2
• Critical safety consideration: Microfilarial load must be assessed before treatment
  • Safer when microfilarial count <8000 mf/ml 2
  • Risk of severe adverse reactions (including Mazzotti reaction) increases with higher parasite loads 2

Key Administration Points

Timing and Food Interactions:

• Always administer on empty stomach with water 1
• High-fat meals increase bioavailability approximately 2.5-fold, which may increase adverse effects 1

Pharmacokinetics:

• Plasma half-life: approximately 18 hours 1
• Peak concentrations occur approximately 4 hours post-dose 1
• Metabolized primarily by CYP3A4 in the liver 1

Safety Considerations

Common Pitfalls to Avoid:

• Never use in Loa loa co-infection without careful microfilarial assessment - risk of severe encephalopathy 2
• Check for concomitant onchocerciasis in loiasis patients, as treatment algorithms differ 2
• Avoid in patients with severe liver disease 3
• Contraindicated in pregnancy and breastfeeding 3

Drug Interactions:

• Monitor patients on CYP3A4 inhibitors or inducers 1
• Avoid concurrent use with other drugs that may lower seizure threshold

Weight Threshold:

• Minimum weight for treatment: 48 kg 3
• Your patient is at the exact minimum threshold - ensure accurate weight measurement

Clinical Monitoring

After treatment, monitor for:

• Adverse events (headache most common across all indications) 3
• Treatment efficacy through appropriate follow-up testing (stool exams for strongyloidiasis, skin snips for onchocerciasis) 1
• In loiasis: close observation for neurological symptoms if microfilarial load was elevated 2

The ivermectin dose calculation is straightforward for this 48 kg patient, falling precisely at the lower weight threshold in FDA dosing tables, making 3 tablets (9 mg total) the definitive dose for strongyloidiasis and the appropriate starting point for other indications 1.