Ep. 12: Start Low and Go Slow: Understanding Psychotropic Drug Interactions

Dr. Merrill Norton provides an in-depth look at psychotropic drug interactions and what clinicians need to understand to prescribe safely in this episode of Psychopharmacology Today. He explains the distinction between pharmacokinetic interactions (what the body does to a drug) and pharmacodynamic interactions (what drugs do to the body), with particular attention to the CYP450 enzyme system, renal clearance, protein binding, and pharmacogenomic differences.

Dr. Norton highlights high-risk combinations involving opioids, benzodiazepines, antidepressants, antipsychotics, stimulants, and mood stabilizers, while exploring potentially serious complications including respiratory depression, serotonin syndrome, QT prolongation, seizures, anticholinergic toxicity, and lithium toxicity. He also addresses the added complexity of treating patients with co-occurring mental health and substance use disorders, emphasizing medication reconciliation, patient-specific risk assessment, careful monitoring, and patient education.