Usefulness of mineralocorticoid receptor antagonists, rather than angiotensin II receptor blockers, for the prevention and treatment of licorice-induced pseudoaldosteronism

Aim The influence of angiotensin II receptor blockers (ARB) on licorice-induced pseudoaldosteronism remains unclear and the antihypertensive drug selection of prescribers, when they encounter hypokalemia and hypertension in licorice-treated patients, has not been surveyed. Methods We examined the occurrence of hypokalemia, concomitant drugs, and treatment for hypokalemia and hypertension in 42, 26 and 27 patients prescribed the licorice-containing traditional Japanese kampo medicines shakuyakukanzoto (SKT; containing 6 g licorice/day), rikkunshito (RKT; 1 g licorice/day), and goshajinkigan (GJG; without licorice), respectively. Results Seven (16.7%; P  < 0.05) of 42 patients treated with SKT more than 4 weeks developed hypokalemia. This rate was significantly higher than that in the GJG group as a negative control. Only one (3.8%) of 26 patients treated with RKT developed hypokalemia. None of the five patients who received simultaneous SKT and mineralocorticoid receptor (MR) antagonists developed hypokalemia. In contrast, four (57.1%) of seven patients who developed hypokalemia were treated with simultaneous SKT and ARB. Conclusion MR antagonists may be useful for both the prevention and treatment of pseudoaldosteronism, while ARB may not be.