Digoxin Quiz

Question 1

As you might expect from understanding the mechanism of action for digoxin this medication is cleared from the body via metabolism. However about 30% of digoxin is cleared by the kidney. Also it is known that renal failure by itself can impair the activity of Na-K-ATPase.

Based upon the above statements which response is correct?

A) Patients having renal insufficiency and also taking digoxin should be monitored carefully for safety and efficacy. It may be necessary to reduce the dose of digoxin in proportion to the reduced renal function to prevent serious digoxin toxicity.
B) Patients having renal insufficiency and also taking digoxin need not be monitored carefully for safety and efficacy. For most patients it will not be necessary to reduce the dose of digoxin to prevent serious digoxin toxicity.
C) Patients having renal insufficiency and also taking digoxin need not be monitored carefully for safety and efficacy. For most renal patients it will be necessary to dramatically increase the dose of digoxin to preserve digoxin efficacy.
D) Patients having renal insufficiency and also taking digoxin need not be monitored carefully for safety and efficacy. For most renal patients it will be necessary to add another medication that interferes with the metabolism of digoxin so that the effect of digoxin on Na-K-ATPase is enhanced.

Answer 1

A

Question 1

Which statement is NOT correct?

A) Digoxin interferes with Na-K-ATPase in cardiac tissue. The resulting increase in intracellular sodium acts to inhibit the efflux of calcium
B) Digoxin has a very narrow therapeutic index, adverse effects can be frequent and severe if patients are not monitored carefully
C) Digoxin acts as a vagolytic
D) Digoxin is rarely considered a first line drug due to its narrow therapeutic window, and lack of benefit on mortality. However in carefully selected patients, adding digoxin can improve cardiac contractility, reduce hospitalizations and reduce patient symptoms of heart failure

Answer 1

C - digoxin interferes with Na-K-ATPase in cardiac tissue. The resulting increase in intracellular sodium acts to inhibit the efflux of calcium. Digoxin has a very narrow therapeutic index, adverse effects can be frequent and severe if patients are not monitored carefully. Digoxin is rarely considered a first line drug due to its narrow therapeutic window, and lack of benefit on mortality. However in carefully selected patients, adding digoxin can improve cardiac contractility, reduce hospitalizations and reduce patient symptoms of heart failure.

Digoxin acts as a vagoTONIC.