Digoxin Flashcards
Class
Cardiac stimulant
Actions
Slows heart Slows AV conduction Prolongs AV node refractory period Increases force of contraction in failing heart
Mechanism of action
Inhibits Na+/K+ ATPase in plasma membrane Increased intracellular Na+ reduces Ca2+ extrusion thus increasing Ca2+
Clinical use
Atrial fibrillation
Heart failure
Adverse effects
Dysrhythmias
Yellow vision
Nausea
Vomiting
what is Digoxin
A cardiac glycoside (A Sodium potassium ATPase inhibitor)
what is digoxin used to treat
used to treat congestive heart failure, and supraventricular arrhythmias
mode of action of Digoxin
via inhibition of the Na-K-ATPase membrane pump, resulting in an increase in intracellular sodium. This causes in turn the sodium calcium exchanger (NCX) to extrude the sodium and pump in more calcium.
what happens as a result of the alteration in calcium concentration?
is thought to promote activation of contractile proteins (e.g., actin, myosin).
other than the meberance pumpl, wha else does digoxin act on
Digoxin also acts on the electrical activity of the heart, increasing the slope of phase 4 depolarization, shortening the action potential duration, and decreasing the maximal diastolic potential.
current usage?
Still used in Atrial Fibrillation, but now very much third line treatment option
is digoxin still used in heart failure
no because better drugs aavailabe