magnesium sulfate + digoxin

A combination of **magnesium sulfate** and **digoxin** may be administered in specific clinical scenarios involving cardiac arrhythmias, particularly in the context of digoxin toxicity or rapid atrial fibrillation. **Digoxin** is a cardiac glycoside that inhibits sodium/potassium-transporting ATPase, leading to increased intracellular calcium and thus increased myocardial contractility and vagal tone, used to treat heart failure and atrial fibrillation[1][6]. **Magnesium sulfate** is an electrolyte and antidote that stabilizes excitable membranes by facilitating calcium, potassium, and sodium transport and can directly suppress arrhythmias, especially those provoked by digitalis (digoxin) toxicity[2][4]. Magnesium sulfate acts as an antidote to digoxin toxicity by stabilizing the heartbeat, suppressing early after depolarizations, and influencing calcium and potassium fluxes across the myocardial cell membrane[2][3][7]. Combined use (e.g., for rapid ventricular rate in atrial fibrillation or digoxin toxicity) is sometimes employed when immediate control of arrhythmia is required, especially if digoxin antibodies are not available[5][3][9].