Digoxin is a cardiac glycoside that inhibits the sodium-potassium ATPase pump in heart muscle cells. This leads to increased intracellular calcium, strengthening heart contractions (positive inotropy) to improve cardiac output in heart failure. It also slows electrical conduction through the atrioventricular (AV) node, helping to control rapid heart rates in conditions like atrial fibrillation.
Verdict
A legacy drug for heart failure/AFib requiring strict medical supervision.
HEALTHSPAN IMPACT
Moderate
RISK LEVEL
High
EVIDENCE GRADE
A
MONTHLY COST
$10 - $30
Protocol
- Typically administered as a low daily oral dose, such as 0.125 to 0.25 mg.
- Dosing is highly individualized and requires therapeutic drug monitoring to maintain safe blood levels.
Flags
- Has a very narrow therapeutic window, where toxic doses are close to therapeutic doses.
- Risk of digitalis toxicity, which can cause nausea, vision changes, and fatal arrhythmias.
- Requires regular blood tests to monitor drug levels, kidney function, and electrolytes.
- Numerous significant drug interactions, including with common diuretics, antibiotics, and other heart medications.
- Risk of toxicity is significantly increased by low potassium or magnesium levels.