Digoxin (better known as Digitalis), sold under the brand name Lanoxin among others, is a medication used to treat various heart conditions. Most frequently it is used for atrial fibrillation, atrial flutter, and heart failure. Digoxin is one of the oldest medications used in the field of cardiology. It works by increasing myocardial contractility, increasing stroke volume and blood pressure, reducing heart rate, and somewhat extending the time frame of the contraction. Digoxin is taken by mouth or by injection into a vein. Digoxin has a half life of approximately 36 hours given at average doses in patients with normal renal function. It is excreted mostly unchanged in the urine. Common side effects include breast enlargement with other side effects generally due to an excessive dose. These side effects may include loss of appetite, nausea, trouble seeing, confusion, and an irregular heartbeat. Greater care is required in older people and those with poor kidney function. It is unclear whether use during pregnancy is safe. Digoxin is in the cardiac glycoside family of medications. It was first isolated in 1930 from the foxglove plant, Digitalis lanata. It is on the World Health Organization's List of Essential Medicines. In 2020, it was the 237th most commonly prescribed medication in the United States, with more than 1million prescriptions. Medical uses Irregular heartbeat The most common indications for digoxin are atrial fibrillation and atrial flutter with rapid ventricular response, though beta blockers and/or calcium channel blockers may be preferred in some patients, such as those without heart failure or hemodynamic instability. Some reviews suggest that digoxin increases the risk of death, while others suggest no change in mortality. It has been suggested that the effect on mortality seen in some studies was due to inappropriately high doses of digoxin and that the low doses often used in practice (levels <0.9 ng/mL) may not increase mortality. Cardiac arrhythmias may also occur when patients are prescribed digoxin alongside thiazides and loop diuretics. Heart failure Digitalis (i.e. extracts, including digoxin, from the plant genus digitalis) was the first drug used to treat dropsy (swollen ankles—a symptom of heart failure) following its discovery by William Withering. Alongside diuretics, it was the mainstay of treatment for heart failure for over a century. Since the introduction of other drugs with better outcomes and fewer adverse effects, it is generally now only used where heart failure is associated with atrial fibrillation