Aldactone (spironolactone 25mg, 50mg, 100mg) is a medication that is primarily used to treat high blood pressure (hypertension). Therapy is usually started at a dose of 25mg twice a day. It works as a diuretic causing increased amounts of sodium and water to be excreted from the body, while potassium is retained.
Because of its ability to retain potassium, the medication can elevate the blood levels of potassium to dangerous levels (hyperkalemia). It should, therefore, only be used under a doctor’s supervision.
Spironolactone has anti-androgenic affects and has been used in the treatment of hair loss in women. It is a weak competitive inhibitor of the binding of androgens to their cellular receptors and decreases the synthesis of testosterone
Studies suggest that spironolactone requires at least 200mg/day for stopping loss and that it has little effect on regrowth of hair. Unfortunately, this dose is high enough to elevate potassium levels and place the patient at risk of hyperkalemia and other side effects, including cramps and diarrhea.
Since spironolactone is an anti-androgen (inhibits testosterone), it causes sexual dysfunction and breast enlargement in men. Because of these side effects, it is not used as a treatment for male pattern alopecia.