Digoxin

Question 1

Ther

Pharm

Answer 1

Antiarrhythmics; Inotropics

Digitalis Glycosides

Question 2

Indications

Answer 2

Heart Failure
A. Fib and A. Flutter (Slows ventricular rate)
Paroxysmal atrial tachycardia

Question 3

Action

Therap.

Answer 3

Increases the force of myocardial contraction
Prolongs refractory period of the AV node
Decreases conduction through the SA and AV nodes
-Increased CO (+ inotropic effect) and slowing of the heart rate

Question 4

CAUTIONS

Answer 4

Use cautiously in: 
Hypokalemia- increase risk of toxicity
Hypercalcemia -increase risk of toxicity 
Hypomagnesemia- same
MI

Question 5

Side Effects

Answer 5

Fatigue 
Headache 
Weakness
ARRHYTHMIAS 
Bradycardia
ECG changes -AV block 
Anorexia 
Nausea Vomiting 
Diarrhea
Thrombocytopenia

Question 6

Drug Drug interaction

Answer 6

Thiazide/Loop Diuretics
corticosteroids and exc. use of laxatives may cause hypokalemia which increase risk for toxicity
-Amiodarone may increase levels

Question 7

Toxicity Overdose

Answer 7

Therapeutic serum digoxin levels range from 0.5-2ng/ml
Serum levels may be drawn 6-8 hr after a dose is administered ; although they are drawn immediately before the next dose.

FIRST SIGNS:
Abdominal Pain 
anorexia
N/V
visual disturbances
bradycardia and other arrhythmias 

Antidote: DIGIBIND
binds to the digitalis glycoside molecule in the blood and is excreted by the kidneys