Spironolactone is a potassium-sparing diuretic medication that is primarily used to treat fluid build-up due to heart failure, liver scarring, or kidney disease. It is also used in the treatment of high blood pressure, low blood potassium that does not improve with supplementation, early puberty in boys, acne, and excessive hair growth in women, and as a part of transgender hormone therapy in transgender women. Spironolactone is taken by mouth.
Common side effects include electrolyte abnormalities, particularly hyperkalemia, nausea, vomiting, headache, rashes, and a decreased libido. In those with liver or kidney problems, extra care should be taken. Spironolactone has not been well studied in pregnancy and should not be used to treat high blood pressure of pregnancy. It is a steroid that blocks the effects of the hormones aldosterone and testosterone and has some estrogen-like effects.