Mycobacterium avium Complex (MAC)

November 2004     View PDF     En español

Drug interactions

Interactions may occur between clarithromycin and rifabutin. Rifabutin can decrease clarithromycin levels in the blood by 50%, while clarithromycin can increase rifabutin levels by as much as 80%. Fluconazole, an anti-fungal drug, can also increase rifabutin levels by up to 80%. Increased levels of rifabutin could cause more severe side effects like uveitis. It’s important to talk to your doctor about potential drug interactions.

Rifabutin and clarithromycin may interact with protease inhibitors (PIs). Azithromycin is not thought to interact with PIs so it may be the best choice for people taking a protease inhibitor.

In general, people taking PIs should avoid rifabutin. If a person has to take rifabutin, indinavir is the PI of choice, and the dose of rifabutin should be cut in half. Rifabutin may also interact with some non-nucleoside reverse transcriptase inhibitors.

Although PIs might also raise clarithromycin levels, there are not enough data on this to say whether the dose of either drug should be changed. Clarithromycin may also decrease blood levels of AZT. For more details about interactions of anti-MAC treatments with other drugs, read Drug Interactions.