Amiodarone and Digoxin: Drug Interaction Explained

The amiodarone and digoxin drug interaction is one of the most clinically important cardiovascular drug interactions to understand because it can raise digoxin exposure and increase the risk of digoxin toxicity.In this episode of This Is Why, Dr. Busti explains why amiodarone can increase digoxin concentrations, how P-glycoprotein inhibition changes digoxin handling, and why clinicians should anticipate the need for digoxin dose adjustment and monitoring rather than react after symptoms appear.You’ll learn why this interaction is not just a memorized warning, but a predictable pharmacokinetic and pharmacodynamic issue involving drug transport, renal elimination, cardiac conduction, and patient-specific monitoring.Topics Covered:Why digoxin has a narrow therapeutic windowHow P-glycoprotein affects digoxin absorption and eliminationWhy amiodarone increases digoxin exposureClinical signs of digoxin toxicityWhy nausea, fatigue, confusion, and bradycardia matterHow to think through dose reduction and monitoringWhy renal function and serum concentrations matterAdditive electrophysiologic effects on heart rate and conductionHow understanding the mechanism improves patient careWhen we understand the why, we improve the how.👉 Get more with a free membership at https://www.thisiswhy.health/Access free downloads from our videosAccess deep-dive content from Dr. BustiOrganize content via playlists & collectionsJoin live Q&AReceive member newslettersCoupons & discounts for exam prep resourcesChapter Table of Contents00:00 - Introduction01:49 - Digoxin's Narrow Therapeutic Index02:31 - P-Glycoprotein: The Key Transporter04:53 - How Amiodarone Inhibits P-Glycoprotein06:37 - Clinical Signs of Digoxin Toxicity08:27 - Managing the Interaction09:59 - Pharmacodynamic Effects on Cardiac Conduction11:19 - Key Clinical Takeaways👍 If this helped you, please like, subscribe, and share it with a classmate or colleague. That will help this new channel continue producing free, high-yield medical education content.🔔 Don’t forget to turn on notifications so you don’t miss upcoming lectures in pharmacology, medical rounds, and more!#Amiodarone #Digoxin #DrugInteraction #DigoxinToxicity #PGlycoproteinSpeaker:Anthony Busti, MD, PharmD, MSc, FAHA, FNLA, is a licensed healthcare professional and medical educator with over 30 years of experience in clinical practice and academic teaching. He has trained and practiced as a nurse, pharmacist, and physician, bringing a uniquely comprehensive perspective to patient care and medical education.Dr. Busti is dedicated to advancing evidence-based medicine and helping clinicians understand the underlying “why” behind clinical decisions to improve patient outcomes.About This Channel:This content is created by Anthony Busti, MD, PharmD, MSc, FAHA, FNLA, a board-certified physician with training at Johns Hopkins School of Medicine and University of Oxford and a medical educator for healthcare professionals and students. All material is based on current medical literature and evidence-based guidelines that align with principles of evidence-based medicine (EBM) and Evidence-Based Healthcare (EBHC).Disclaimer:This content is for educational purposes only and is not medical advice. It does not replace individualized evaluation, diagnosis, or treatment. Always seek the advice of a qualified health provider with questions about a medical condition and never delay care because of educational content.