Sulfamethoxazole-trimethoprim (cotrimoxazole) is an antibiotic combination widely used for infections treatment and prophylaxis. These and others sulfonamides have been implicated in a rare syndrome of choroidal effusion with transient myopia and angle-closure glaucoma. Previous cases reported in literature evolved to complete resolution after drug withdrawal. In contrast, we describe a rare case in which a patient developed the syndrome while taking cotrimoxazole, but did not recover visual acuity. A 49-year-old man started Pneumocystis carini prophylaxis with cotrimoxazole; four days later, the patient presented severe ocular pain, hyperemia and chemosis. Intraocular pressure reached more than 50 mmHg in both eyes a 360 degrees choroidal effusion occurred. Medication was removed soon after the diagnosis was suspected and intraocular pressure decreased in four days. Even so total cataract and phthisis bulbi occurred in both eyes two months later. This would be the first case in the literature in which the outcome was unfavorable despite early diagnosis and withdrawal of the drug.