Loxoscelism is a condition produced by the bite of Loxosceles laeta. It can present as cutaneous loxoscelism with only vascular dermal manifestations or as viscerocutaneus loxoscelism with systemic compromise and a mortality rate of 1 to 3%. We report the case of an adult patient presenting viscerocutaneus loxoscelism, who was evolving with macrohematuria, edema, and progressive blisters, requiring treatment in the intensive care unit. He was treated according to the actual scientific evidence with antihistamines, corticosteroids, and dual antibiotic therapy covering Streptococcus spp., Staphylococcus spp., and anaerobes, particularly penicillin and tetracycline resistant C. perfringens. The use of dapsone and antiloxosceles-serum was avoided. The patient showed a favorable clinical evolution.