Glycosides

Question 1

Drug of choice for treatment of CHF

Answer 1

digoxin** (Digitek, Lanoxin)

Question 2

Indications digoxin** (Digitek, Lanoxin)

Answer 2

CHF and atrial

fibrillation/flutter

Question 3

Mechanism of Action Indications digoxin** (Digitek, Lanoxin)

Answer 3

 Inhibits Na/K ATPase pump
– results in increased Ca+ inside of cell
 Increases contraction of the heart***
 Positive inotropic effect

---Causes diuresis***
 Decreases venous return
 Allows heart to become more efficient
 Decreases filling pressure
 Decreases heart rate
 Decreases heart size

Question 4

Problems with Cardiac Glycosides

Answer 4

 Increased vagal output = can be blocked by
atropine (anticholinergic drug)

 Slowing of AV conduction = can slow too
much, which allows for ectopic foci =
uncoordinated arrhythmias*** can arise

 Low therapeutic index = therapeutic dose is
approximately 50-60% of the toxic dose
– Every patient must be titrated

Question 5

Digoxin Toxicity Glycosides

Answer 5

 Central Nervous System

– Headache = vasodilation, changes in edema in CNS
– Fatigue = decreased muscle tone (parasympathetic
effect makes you feel fatigue)
– Drowsiness – Visual disturbances (blurry vision)
– Green/yellowish aura*** = patient knows that he is at
toxic level of digitalis if he sees this aura
 A favorite Board exam question

Question 6

Level of digoxin may be increased by

concurrent use of

Answer 6

ed flag drugs in dentistry:

Question 7

Digoxin effects

Answer 7

Decreases heart rate which increases filling time
– Increases force of contraction so that it can increase
ejection fraction