Efavirenz
From SNPedia
Efavirenz, a trade name for a drug sold under the brand name Sustiva among others, is an antiretroviral drug used in the treatment of human immunodeficiency virus (HIV) infection. Certain variants, such as several in the CYP2B6 gene, may be associated with poor metabolism of efavirenz and as a result increased risk for central nervous system (CNS) adverse effects.Wikipedia