Multiple adverse drug reactions and genetic polymorphism testing: A case report with negative result

RATIONALE: Defects in drug metabolic pathways could explain why some patients have a history of multiple adverse drug reactions (ADR); therefore we aimed to analyze genetic polymorphisms in a patient with multiple ADR related to drugs with a common hepatic metabolic pathway through CYP2D6. PATIENT CONCERNS: We report a patient with psychosis and hypertension related to amitriptyline, tramadol, and duloxetine within a 2-year period. INTERVENTIONS AND OUTCOMES: A pharmacogenetic test was performed to assess the causative role of the CYP2D6 enzyme, but did not demonstrate a metabolic deficiency. LESSONS: Although negative results in the reported case; typing for cytochrome P450 isoenzyme polymorphisms could be a useful diagnostic tool in some patients with a history of multiple ADR.