This result signifies that the patient has two copies of a no function allele (*_/*_). Based on the genotype result this patient is predicted to be a poor metabolizer of CYP2D6 substrates. This patient may be at a high risk for an adverse or poor response to medications that are metabolized by CYP2D6. To avoid an untoward drug response, dose adjustments or alternative therapeutic agents may be necessary for medications metabolized by the CYP2D6. Please consult a clinical pharmacist for more information about how CYP2D6 metabolic status influences drug selection and dosing.