Question

65 year old with nonischemic cardiomyopathy treated with furosemide carvedilol, lisinopril, and digoxin comes to ER with palpitations. EF 35%, BP 160/100, pule 130 and irregular. He has a fib and is put on rivaroxaban and amiodarone. Two weeks later he presents with profound anorexia, nausea, and generalized weakness why?

- Digoxin + Amiodarone causes acute digoxin toxicity. Amiodarone increases digoxin serum levels. Must decrease dose by 25-50% before initiating amiodarone

Answer 1

The patient displays symptoms consistent with acute digoxin toxicity, likely caused by the interaction between digoxin and amiodarone that led to increased digoxin levels in the blood. Medication doses need to be adjusted when used in combination to avoid such toxicity.

Step-by-step explanation:

The patient in the scenario likely experiences acute digoxin toxicity due to the combination of digoxin with amiodarone, which is known to increase digoxin serum levels. Physicians typically need to reduce the digoxin dosage by 25-50% when initiating amiodarone to prevent toxicity. Symptoms of digoxin toxicity include anorexia, nausea, and generalized weakness, which align with the patient's presentation.

Digoxin acts as a positive inotropic agent by increasing intracellular calcium levels, leading to a stronger heart contraction. Amiodarone, on the other hand, is used to treat arrhythmias such as atrial fibrillation, which the patient has. An interaction between these drugs can greatly enhance the effect of digoxin, necessitating careful monitoring and dose adjustment to prevent adverse effects.