Onchocerciasis (river blindness) is the second leading infectious cause of blindness globally — and Ivermectin is its FDA-approved treatment, taken annually at 150 mcg/kg. The Nobel Prize in Medicine 2015 was awarded partly for Ivermectin's discovery and its impact on this disease. This complete guide covers the blackfly transmission cycle, the skin and eye symptoms, how to diagnose it in returned travellers, the weight-based dosage table, and the expected Mazzotti reaction a