What is the appropriate prophylaxis for Toxoplasmosis in a patient with a CD4 count less than 100?

The appropriate prophylaxis for Toxoplasmosis in a patient with a CD4 count less than 100 is double strength Bactrim. In individuals with advanced HIV/AIDS, a CD4 count less than 100 cells/mm³ significantly increases the risk for opportunistic infections, including Toxoplasmosis, which is caused by the parasite Toxoplasma gondii.

Double strength Bactrim (trimethoprim-sulfamethoxazole) is the first-line prophylactic treatment for Toxoplasmosis in these patients. It has been extensively studied and shown to effectively reduce the incidence of Toxoplasmosis in immunocompromised individuals. The combination of trimethoprim and sulfamethoxazole works synergistically to inhibit folic acid synthesis in the parasite, making it an effective prophylactic choice.

Single strength Bactrim would not provide sufficient coverage, as the dosing used for prophylaxis typically requires a higher concentration of the medication to be effective. Other alternatives such as Dapsone and Clindamycin are used in specific cases or when patients are intolerant to Bactrim, but they are not the standard initial prophylactic choices for Toxoplasmosis in patients with a CD4 count below 100.