{"6-mercaptopurine can be affected by a patient's TPMT and NUDT15 phenotype. This patient is predicted to be a TPMT poor metabolizer and NUDT15 normal metabolizer. This patient is at high risk for life threatening myelosuppression with normal doses of 6-mercaptopurine and should receive greatly reduced doses. For malignancy, start with reducing the normal single dose for 6-mercaptopurine by 90% and administer three times a week (e.g., 10 mg/m2/day given just 3 days/week) and adjust doses of mercaptopurine based on degree of myelosuppression and disease-specific guidelines. Allow 4-6 weeks to reach steady-state after each dose adjustment. If myelosuppression occurs, emphasis should be on reducing mercaptopurine over other agents. For non-malignant conditions, consider alternative non-thiopurine immunosuppressant therapy. Please consult a clinical pharmacist for more information."}