CYP2D6 a member of the cytochrome P450 superfamily of enzymes. CYP2D6 plays a vital role in the metabolism of a wide range of drugs and environmental chemicals, influencing the pharmacokinetics of over 30 different medications, including many commonly prescribed drugs. CYP2D6 is primarily located in the liver, where CYP2D6 facilitates the oxidative metabolism of xenobiotics, making CYP2D6 essential for drug detoxification and clearance from the body. This localization is crucial because this placement underscores the liver′s role as the body′s primary metabolic organ, where CYP2D6′s enzymatic activity can significantly affect drug efficacy and safety. Variations in CYP2D6 activity due to genetic polymorphisms can lead to altered drug responses, which is particularly important in personalized medicine, as these variations can help predict patient responses to medications and reduce the risk of adverse drug reactions.