Which of the following medications is used for treatment of HIV-associated infections when there's an allergy to TMP-SMX?

Dapsone is an appropriate choice for treating certain infections in patients with HIV who have an allergy to TMP-SMX (trimethoprim-sulfamethoxazole). TMP-SMX is commonly used to prevent and treat Pneumocystis jirovecii pneumonia (PCP), which is an opportunistic infection associated with HIV.

Dapsone is an antibiotic that can effectively be used to treat PCP in patients who cannot tolerate TMP-SMX due to allergy or hypersensitivity reactions. It has a similar mechanism of action and is used as an alternative for those specifically allergic to TMP-SMX.

In contrast, the other options do not serve as suitable substitutes for TMP-SMX in the context of treating HIV-associated infections. Azithromycin is typically used for various bacterial infections, including respiratory infections and some sexually transmitted infections, but it is not effective against PCP. Vancomycin is primarily used for serious gram-positive infections and is not indicated for pneumocystis. Ciprofloxacin is a fluoroquinolone antibiotic more commonly utilized for urinary tract and gastrointestinal infections, not for the treatment of PCP or other HIV-related conditions.

Thus, dapsone stands out as the correct medication in this context, offering an effective alternative for patients with a