Crusted scabies is mainly observed in children with immunosuppression or mental illness. Treatment is very difficult, and relapse is frequent after topical scabicidal therapy. We describe a case of crusted scabies, induced by long-term application of a topical corticosteroid, relapsing after topical treatment and dramatically improved by ivermectin. We suggest that ivermectin is a safe and effective alternative therapy for the treatment of severe Sarcoptes scabiei infestation in children unresponsive to conventional treatment.