Digoxin is a cardiac glycoside derived from the digitalis plant，used primarily in the treatment of heart failure and arrhythmias such as chronic heart failure and atrial fibrillation^[1]. It exerts positive inotropic and atrioventricular node inhibitory effects by inhibiting the sodium-potassium ATPase pump in cardiomyocytes, which enhances myocardial contractility and slows heart rate ^[2].

Digoxin faces many challenges in clinical application, including the following: narrow therapeutic window: the therapeutic window of digoxin is very narrow, and its effective dose is close to the toxic dose. It is generally recognized that the therapeutic concentration range of digoxin is 0.8-2.0 ng/mL, and exceeding 2.4 ng/mL is considered toxic. However, reference ranges may vary between laboratories and there are significant differences in individual responses to digoxin, which adds to the complexity of clinical dosing^[2]. In addition, factors such as age, renal function, and coadministration can affect the pharmacokinetics of digoxin, with older patients and those with renal insufficiency more susceptible to toxicity. Adverse reactions are numerous: digoxin has a large number of adverse reactions, including gastrointestinal reactions (e.g., nausea, vomiting, diarrhea), central nervous system symptoms (e.g., headache, dizziness, visual abnormalities), and cardiotoxicity (e.g., cardiac arrhythmias). Of these, cardiotoxicity is the most serious and can lead to fatal arrhythmias. In addition, digoxin poisoning may manifest as hypotension, weakness, and confusion. Drug interactions are complex: Digoxin interacts with a variety of drugs, which may affect its efficacy or increase the risk of toxicity. For example, azole antifungals and macrolide antibiotics may inhibit digoxin metabolism and increase its blood concentration, while laxatives and enzyme inducers may decrease its blood concentration^[3]. In addition, digoxin may increase the risk of adverse reactions when combined with calcium and calcium channel blockers. Difficulty in the diagnosis and management of poisoning: the lack of specificity in the signs and symptoms of digoxin poisoning and the unclear diagnostic criteria for poisoning pose a great challenge to clinicians^[3]. In addition, the management of poisoning requires comprehensive consideration of a variety of factors, such as the duration of poisoning, the type of poisoning (acute, chronic, etc.), and the need for digoxin-immunized Fab. In conclusion, the clinical application of digoxin requires comprehensive consideration of the individual patient's condition, renal function, coadministration and other factors, as well as strict monitoring of blood concentrations to ensure its safety and efficacy.