Gene CYP2B6
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Also known as
CPB6, EFVM, IIB1, P450, cytochrome P450 family 2 subfamily B member 6Overview
CYP2B6 (Cytochrome P450 Family 2 Subfamily B Member 6) encodes a hepatic enzyme that metabolizes a clinically important set of drugs including the HIV medication efavirenz, the smoking cessation drug bupropion, the anesthetics propofol and ketamine, and the antimalarial artemether. CYP2B6 is highly inducible by drugs and environmental chemicals.CYP2B6 is highly polymorphic with substantial variation between populations. The CYP2B6*6 allele (containing two key variants) is very common and causes reduced enzyme activity. Poor metabolizers of efavirenz have higher drug levels leading to increased CNS side effects, prompting dosing guidelines. The CYP2B6*18 allele, common in African populations, is associated with even more severely reduced activity.
Understanding your CYP2B6 genetic status is important for pharmacogenetic-guided prescribing of efavirenz in HIV treatment, optimizing bupropion dosing for smoking cessation or depression, and potentially for anesthetic drug selection. This gene is included in clinical pharmacogenetic testing panels.