Severe co-trimoxazole reaction in a man with AIDS.

Although other drugs can be used in the prophylaxis and treatment of HIV-infected persons, family physicians will prescribe co-trimoxazole frequently. These providers need to recognize the overall increased frequency of adverse reactions to this drug in this population and the potential for severe hypersensitivity effects requiring intensive hospital care. While the exact importance re-exposure has in causing this reaction remains unclear, certainly providers must pay particular attention to patients who have had any earlier sensitivity to the drug before treatment is resumed. Desensitization therapy has been used successfully in some HIV-positive individuals, even after severe reactions; however, this case again teaches the need for prudence in the use of all pharmacological agents.