The roll-out of life saving antiretroviral medication has improved the quality
of life and increased the life expectancy of HIV-infected individuals. HIV-infected
individuals suffer more ailments compared to the general population, necessitating
frequent co-medications. There is considerable geographic overlap between areas with
high prevalence of HIV and other infectious diseases such as malaria, tuberculosis, and
neglected tropical diseases raising the possibility of complex polypharmacy and drugdrug
interactions. The cytochrome P450 (CYP450) enzymes play a major role in
metabolism of many of the ARVs and drugs used for the treatment of other prevalent
diseases; thus co-treatment creates potential for CYP450 mediated drug interactions.
Some ARVs pose a particularly high-risk for potential drug-drug interactions, which
may be pharmacokinetic or pharmacodynamic in nature and can result in raising or
lowering plasma or tissue concentrations of co-prescribed drugs. Elevated drug
concentrations may be associated with drug toxicity and lower drug concentrations may
be associated with therapeutic failure. This chapter provides an in-depth understanding
of clinically relevant drug-drug interactions during treatment of HIV and common
illnesses and reviews the currently available data on interactions between ARVs and
drugs used in the management of some other common illnesses.
Keywords: HIV/ART, Concomitant Treatment, AIDS-related Diseases, Cotreatments,
HAART, drug interactions, NNRTI, CYP540, HIV and Cancer, HIV
and Malaria, Rifampicin.
