Psychiatric implications of medications used in human immunodeficiency virus disease

Between four and seven percent of patients admitted to psychiatric hospitals are infected with Human Immunodeficiency Virus (HIV). Psychiatric patients are at a higher risk for developing HIV because they are more likely to engage in high-risk sexual behaviors, have higher rates of substance abuse than other populations, and are less knowledgeable about AIDS. HIV positive patients are at increased risk for adverse drug reactions; therefore, psychiatrists need to be aware of potential neurologic and psychiatric adverse effects of medications commonly used for HIV. For example, many of the common adverse effects associated with agents used in the treatment of HIV mimic signs and symptoms of depression. Also, antiretroviral therapy is rapidly changing and several new agents have become available. It is imperative for psychiatrists to be aware of drug interactions between psychotropic agents and antiretrovirals, particularly the protease inhibitors. The potential for drug interactions is significant because more than half of the psychotropic agents available today as well as five of the eleven HIV agents described in this article are metabolized by or affect drug metabolism through the Cytochrome P450 system. Collaboration with the patients' other prescribers or pharmacists and knowledge of all concurrent medications the patients are taking are the key to preventing adverse events because of drug interactions.