Hypokalemia and hypothyroidism

An 85-year-old man is brought in by his wife. She explains that he is having nausea, vomiting, and some visual changes. During the history, you find out that the patient has multiple medical prob*lems including depression, congestive heart fail*ure, BPH, and hypothyroidism. He was recently started on a "water pill." His other medications are "for my heart," "for my thyroid," "hormone for my prostate," and aspirin. Laboratory analysis shows a serum sodium of 142 mEq/L and potassi*um of 3.0 mEq/L. Which of the following drugs is most likely responsible for his symptoms?

A. Prozac (fluoxetine)
B. BuSpar (buspirone)
C. Digoxin
D. Proscar (finasteride)
E. Thyroxin

C. Digoxin

[sweetsmitha]

yes hypokalemia will increase digoxin toxicity because digoxin and potassium compete with each other for NA/K ATAP ASE. once there is low K, digitoxicity occurs. The same is the interaction between digoxin and lasix.
But one needs to remember that digoxin is one of the drugs that can lead to hyperkalemia. So, hypokalemia can lead to digoxin toxicity where as digoxin toxicity can lead to hyperkalemia