Digoxin is a cardiovascular agent that is used to treat heart failure and atrial fibrillation. The prescription drug is used to strengthen the heart as well as increase the blood circulation in the body. Digoxin is a cardiac glycosides and is available in brand forms as well. Digoxin is a special medication that treats heart failure and mostly used along with other drugs. The medicine is extracted from the leaves of Digitalis plant, and it works by affecting sodium and potassium inside the heart to produce regular rhythms. Digoxin is mostly used to treat chronic atrial fibrillation, a heart rhythm disorder of the upper chambers of the heart. Digoxin is supplied in the form of capsules or liquid, and thus it should be administered in through the mouth with or without food. Patients with kidney problems should not be treated by Digoxin since the damage might be irreparable. Nausea, dizziness and diarrhea are some of the side effects of Digoxin.