Drug Guide 2000: the antiretroviral agents.

Drug resistance in HIV therapy is a growing problem, and several drugs that were approved in 1999 may be beneficial to patients who are becoming resistant to their current therapy. The most influential causes of resistance are non-adherence, improper prescribing of antiretroviral therapy, and extensive drug exposure. In addition, patients are often infected with HIV strains that are already resistant to certain drugs. The consequences and types of resistance vary for each class of anti-HIV drug. The trend toward simpler dosing and PI-sparing regimens has made adherence easier, but HIV treatment remains complex. In addition, many studies show that patients who are being treated by HIV-experienced physicians do better, live longer, and spend less money on medical care than those managed by less experienced physicians.