cardiac glycoside
3 interactions related to cardiac glycoside
digoxin + st. john's wort
St. John's wort revs up a gut transporter that digoxin depends on for absorption, so combining them quietly drains digoxin from the bloodstream. Because digoxin has so little room to spare, that drop can leave the drug too weak to control your heart.
digoxin + hawthorn
Hawthorn (Crataegus) shares digoxin's cardiac target and can cross-react with the immunoassays used to monitor digoxin, so a serum level may read falsely high or low. Controlled testing shows little change in how much digoxin reaches the bloodstream, so the practical concerns are additive cardiac effects and confounded lab monitoring rather than altered absorption.
digoxin + licorice
Glycyrrhizin in licorice inhibits the kidney enzyme 11-beta-hydroxysteroid dehydrogenase type 2, producing a state of apparent mineralocorticoid excess that causes sodium retention and potassium loss. The resulting low potassium makes the heart more sensitive to digoxin and can trigger toxic arrhythmias even when serum digoxin levels look normal.