Digoxin is a cardiac glycoside used in the treatment of congestive heart failure (CHF), particularly in patients with reduced ejection fraction and persistent symptoms despite standard therapy. It works by increasing the force of heart contractions (positive inotropy) and slowing the heart rate, which can improve symptoms like fatigue and shortness of breath.

Digoxin is not a first-line treatment for CHF, but it may be added in select patients—especially those with atrial fibrillation or who remain symptomatic on ACE inhibitors, beta-blockers, and diuretics. It does not reduce mortality, but it may reduce hospitalizations and improve quality of life. Because of its narrow therapeutic window, close monitoring of blood levels and kidney function is required to avoid toxicity.