Parenteral administration of ivermectin in a patient with disseminated strongyloidiasis

We report the case of a 23-year-old Caribbean man with disseminated strongyloidiasis (co-infected with human T cell lymphotropic virus I/II), severe hypoalbuminemia, and a paralytic ileus. Subcutaneous ivermectin (200 mu g/kg) was administered daily for 14 days because of the inability to effectively administer oral albendazole and oral ivermectin. Three hours after the third daily dose of oral ivermectin, the serum ivermectin concentration was only 0.8 ng/mL, but it increased several fold to 5.8 ng/mL 16 hours after the first dose of subcutaneous ivermectin. During the course of subcutaneous treatment, ivermectin clearance was higher than expected (46.0 L/hour, normal = 31.8 L/hour). This is likely the result of severe hypoalbuminemia since ivermectin is highly protein bound. The ability to achieve adequate levels of ivermectin after oral administration in patients with disseminated strongyloidiasis may be impaired, highlighting the need for alternative routes of administration of ivermectin in these patients.