Use

Cytochrome P450 2D6 (CYP2D6) is a drug-metabolizing enzyme involved in the metabolism of more than 65 clinically important drugs including some antidepressants, anti-psychotics, opioids, beta-blockers, antiemetics, atomoxetine and tamoxifen. Individuals with some variant CYP2D6 alleles may experience a reduced therapeutic response and may be at risk for side effects from drugs that are metabolized by CYP2D6. CYP2D6 genotype information can be utilized to predict CYP2D6 metabolic phenotype, which can be used as an aid in determining a therapeutic strategy for drugs that are metabolized by CYP2D6. For example, CYP2D6 ultrarapid metabolizers may experience exaggerated side effects after the administration of codeine, while poor metabolizers may experience a reduced analgesic effect due to insufficient biotransformation into morphine. In these instances, alternative drugs may be considered.