The cause of hair loss is often cited as the binding of testosterone with the enzyme 5-alpha reductase to produce the more potent hormone, dihydrotestosterone (DHT). An increase of DHT levels in the system causes hair loss because it blocks the passage of essential nutrients vital for the survival of hair follicles. They shrink when they do not receive sustenance from the body. Hair follicles that lose its mass cause the balding to occur.
Products have been developed to combat this condition. Confining the discussion to medical remedies, there are currently two drugs approved by the Food and Drug Authority for actual use. The first is called Finasteride, which is the active ingredient in what is sold under the brand name Propecia. It is an orally ingested medication that acts as a 5-alpha reductase inhibitor to prevent such enzyme from fusing with testosterone. This in turn, would result in the decrease of DHT levels in the body and encourage hair regrowth. The next FDA approved drug is Minoxidil. It active in the topically applied product marketed as Rogaine. This serves to increase the mass of hair strands causing it to appear thicker as well as extend its growth. The physiological explanation on how this is accomplished is scarce. All that is known is that it works by increasing the blood circulation to the hair follicles.
Propecia is recommended for use in the more advanced stages of alopecia. Minoxidil on the other hand is more effective in the early stages of balding.
Having examined how hair loss is generally caused as well as the two FDA approved medications that treat it, a discussion on what Spironolactone is and its effects can be put in better perspective. Spironolactone acts as a DHT blocker that prevents it from binding with the receptors in the hair follicles. Note that Finasteride acts as 5-alpha reductase inhibitor. It blocks the enzyme from combining with testosterone to produce DHT. This being the case, Spironolactone works to prevent the existing DHT in the body from further causing hair loss. Finasteride on the other hand, ensures that no more DHT will be produced. Spironolactone used to be taken orally when it was sold under the name Aldactone. It served as to treat high blood pressure and kidney problems. It was also used to prevent heart attacks and stroke. Aldactone treated water retention and raised potassium to its normal levels in the body. It was however discovered that the drug also had an anti-androgen effect that reduced testosterone levels in the system. The lack of testosterone would also translate to a lack of DHT. This would result in a positive result for male pattern baldness. The side effect however, would be breast enlargement in men as well as the threat of hyperkalemia or too much potassium in the blood that could cause abnormal heartbeat or arrhythmia.
Topically applied Spironolactone does not have the same side effects as the orally ingested Aldactone. In fact, the topically applied Spironolactone works so well that it is often used as a one-two punch combination with Propecia. It helps tremendously in the fight against hair loss because it shields the hair follicles from being attacked by the DHT in the body. Propecia in turn prevents new DHT units from forming by blocking the 5-alpha reductase enzyme from binding with testosterone.