Primary prophylaxis

Drug interactions between HIV and MAC drugs are complex—check for drug interactions before prescribing (see Antiretroviral drug interactions).

Note: Check for drug interactions before prescribing MAC prophylaxis for a person with HIV infection.

Primary prophylaxis for MAC is not recommended for patients who immediately commence antiretroviral therapy. Individuals who do not immediately commence antiretroviral therapy or who have a detectable viral load despite antiretroviral therapy should receive primary prophylaxis for MAC if their CD4 count is less than 50 cells/microlitre. Ensure the patient does not have active MAC infection before starting prophylaxis. Use:

1 azithromycin 1.2 g orally, once weekly mycobacterium avium complex, primary prophylaxis (adult with HIV) azithromycin    

OR

2 clarithromycin 500 mg orally, 12-hourly. For dosage adjustment in adults with kidney impairment, see clarithromycin dosage adjustment. mycobacterium avium complex, primary prophylaxis (adult with HIV) clarithromycin    

Duration of therapy: for patients taking combination antiretroviral therapy with a suppressed HIV viral load, stop primary prophylaxis when the CD4 count is more than 100 cells/microlitre for 3 months.

For patients who were previously initiated on primary MAC prophylaxis and currently have a suppressed HIV viral load on antiretroviral therapy, cease primary MAC prophylaxis.