What is the effect of Digoxin (digitalis glycoside) on blood pressure?

From the Guidelines

Digoxin has minimal direct effects on blood pressure in most patients, and its primary mechanism involves increasing cardiac contractility and slowing heart rate rather than directly altering blood pressure. While primarily used to treat heart failure and atrial fibrillation, digoxin may indirectly help stabilize blood pressure in heart failure patients by improving cardiac output, but it is not considered a primary antihypertensive medication.

Key Points to Consider

• The typical maintenance dose ranges from 0.125-0.25 mg daily, with lower doses (0.125 mg daily or even every other day) often appropriate for elderly patients or those with impaired kidney function 1.
• Blood pressure changes, if they occur, are usually modest and secondary to improved cardiac function.
• Patients should have their digoxin levels monitored periodically (therapeutic range: 0.8-2.0 ng/mL), as toxicity can occur with elevated levels 1.
• The medication's primary mechanism involves inhibiting the sodium-potassium ATPase pump, which increases intracellular calcium and enhances myocardial contractility.
• Importantly, electrolyte imbalances, particularly low potassium, can increase the risk of digoxin toxicity, so potassium levels should be maintained in the normal range during treatment 1.

Clinical Considerations

• Digoxin should be used cautiously in patients taking other drugs that can depress sinus or atrioventricular nodal function or affect digoxin levels, such as amiodarone or beta blockers 1.
• The concomitant use of certain drugs, such as clarithromycin, erythromycin, or quinidine, can increase serum digoxin concentrations and may increase the likelihood of digitalis toxicity 1.
• A low lean body mass and impaired renal function can also elevate serum digoxin levels, which may explain the increased risk of digitalis toxicity in elderly patients 1.

From the FDA Drug Label

Digoxin produces hemodynamic improvement in patients with heart failure. Short- and long-term therapy with the drug increases cardiac output and lowers pulmonary artery pressure, pulmonary capillary wedge pressure, and systemic vascular resistance

• Main effects of digoxin on blood pressure:
  • Lowers pulmonary artery pressure
  • Lowers pulmonary capillary wedge pressure
  • Lowers systemic vascular resistance
• The effect of digoxin on systemic blood pressure is not directly stated in the label, but it can be inferred that it may have a indirect effect by reducing systemic vascular resistance 2

From the Research

Digoxin Effect on Blood Pressure

• The effect of digoxin on blood pressure is not directly addressed in the provided studies, but its use in various cardiac conditions is discussed 3, 4, 5, 6, 7.
• Digoxin is used to treat conditions such as atrial fibrillation, congestive heart failure, and certain cardiac arrhythmias, and it has a narrow therapeutic window 6.
• In patients with atrial fibrillation and heart failure, digoxin may be useful in achieving satisfactory rate control, especially in the presence of hypotension or contraindication to beta-blocker treatment 3.
• However, the use of digoxin has been associated with increased mortality in some studies, particularly in patients with atrial fibrillation without systolic congestive heart failure 5, 7.
• A study comparing digoxin and beta-blocker therapy in atrial fibrillation found that digoxin was associated with increased all-cause mortality, cardiovascular mortality, and non-cardiovascular mortality, as well as reduced quality of life 7.
• The choice of digoxin or beta-blocker therapy had no influence on the incidence of unplanned hospitalizations in patients with atrial fibrillation 7.