Features of Digoxin Toxicity in Atrial Fibrillation and Congestive Heart Failure Patients: A Systematic Review

Digoxin is a cardiac glycoside indicated for the treatment of congestive heart failure, atrial fibrillation or flutter, and certain cardiac arrhythmias. The use of digoxin is limited due to its narrow therapeutic index nature. In high concentrations, digoxin has been associated with toxicity features such as gastrointestinal symptoms, visual effects, and cardiac arrhythmia. This systematic review aims to summarize cases of digoxin toxicity including the risk factors, possible drug-drug interaction with digoxin, and presenting symptoms. A literature search was conducted through PUBMED and Ovid Medline using the keywords "digoxin" and "toxicity". The clinical and laboratory manifestations associated with digoxin toxicity were also noted in this review. The search generated 2399 articles and only 10 articles were included in the final analysis. Four out of 10 cases reported diuretics as a possible interacting medication. The symptoms that were usually reported in most cases were nausea and vomiting, change in vision, bradycardia, and increased serum digoxin level. The main risk factors that could lead to digoxin toxicity were females, elderly (60-91 years old), drug-drug interaction; and renal problems (renal disease/ renal impairment/ renal insufficiency). Digoxin toxicity could occur in either low or normal levels of serum digoxin concentration with the presence of concomitant drugs or could be influenced by underlying risk factors. The most common presenting symptoms of digoxin toxicity included nausea and vomiting, change in vision, and bradycardia.