Spironolactone is a diuretic that increases the amount of water and salt removed from the body via the kidneys, which is why they are commonly referred to as “water pills”. However, this class in particular is the only type of diuretic that helps prevent the body from excreting potassium as well. For this reason, it is used to treat potassium deficiencies as well as lowering blood pressure without lowering potassium levels.
Spironolactone is also an antiandrogen, which means that it reduces the level of male sex hormones (androgens) in the body by preventing an enzyme called 5 alpha-reductase (5aR) from metabolizing into a specific type of androgen called dihydrotestosterone (DHT). DHT can cause baldness by gathering in the hair follicles and interfering with the hair’s nutritional supply, ultimately preventing the hair from growing. A sensitivity to DHT is a genetically-inherited condition that not everyone is susceptible to, which is why not everyone experiences hair loss. For those who do, however, antiandrogens can sometimes prevent further balding by lowering the amount of DHT in the body. This diuretic also binds to receptors in the scalp’s tissues, effectively preventing the DHT from accumulating by arriving there first. Spironolactone prevents hair loss in two distinctly different ways. First, by acting as a blocker. Second, by inhibiting 5aR.
The beneficial effects of spironolactone on female hair loss have been known to the medical community for over ten years now. A comparative study by the United States government tested the effects of spironolactone on forty women and found it equally as effective as cyproterone acetate, another antiandrogenic medication. According to the study, 88% of the women experienced no additional hair loss after using the medication. Overall, only 10% of the women continued to lose hair despite antiandrogenic treatment.
While it possibly would help treat male pattern hair loss, it is not prescribed to males. This is because it interacts with the male physiology in a way that often causes drastic hormonal changes in sex drive and overall appearance. For these reasons, this medication is intended to be used only by women.
A 2012 government study notes that “oral spironolactone has been used for over two decades in the dermatological setting”. In addition, the study concludes that there is “sufficient data to suggest that long-term use of the medication appears to be safe overall”, and with no danger of breast cancer, as previously suggested.
This type of diuretic can cause the following side effects, of which you should notify your doctor:
You should always take this medicine exactly as the label prescribes. If you miss a dose, wait until your next dose and take the regular amount. Never take more of this medication than you have been prescribed.