Future of Medical Treatments of Hair Loss

    Most of today's medicines for treating hair loss have limited effectiveness. Today's medications prescribed to counteract androgenetic alopecia (genetic pattern hair loss), require ongoing use for the benefits of treatment to continue, and these medications have only a limited effect on some patients. And the cost of drugs that must be taken continuously adds up to a large lifetime expense. In the future, as physicians and scientists gain a better understanding of how the normal hair growth cycle is controlled, and how various disease conditions affect hair growth, new medicines will be developed that more effectively target the cause of the hair loss, and cause fewer side effects as a result.

    Perhaps one the most promising "future" medical treatments, which actually is on the market, being prescribed to treat benign enlarged prostate glands, is GlaxoSmithKliines's drug Dutasteride currently being sold under the brand name Avodart. Like Propecia, dutasteride is a 5-alpha-reductase inhibitor taken as a pill, and it has been shown to dramatically reduce the amount of testosterone in the blood from being converted into dihydrotestosterone (DHT). High levels of DHT in the blood over many years can cause enlarged prostate glands in men. DHT in the bloodstream also signals hair follicles to reduce hair growth, causing pattern baldness in people who have inherited hair follicles that are sensitive to DHT.

    Reducing DHT in the blood causes the chemical message to "stop growing hairs" to become weaker, to a degree that it will not affect the susceptible hair follicles. The trick to reducing DHT levels is to use a medication to stop the 5-alpha reductase enzyme from converting testosterone into DHT. If testosterone is not converted to DHT, the DHT message never gets to the cells in the susceptible hair follicles, and these hair follicles will continue to grow new hairs.

   There are two types of 5-alpha-reductase that convert testosterone to DHT. While Propecia effectively blocks the type-II 5-alpha-reductase enzyme, Dutasteride has been shown to effectively block both type-I and type-II 5-alpha-reductase. While Propecia use typically results in a 65-70% decrease in DHT in the blood of men, Dutasteride has been shown to decrease DHT in the blood by 90% or more. I am optimistic that Dutasteride will work better for females with inherited pattern hair loss than any other medication currently available, as well as for men who did not get good results from Propecia. Side effects of Dutasteride are believed to be similar to Propecia, however the dosage appropriate for treating genetic hair loss has not been determined, and side effects are dosage-related.

   One way to increase the effectiveness of hair loss medications, and simultaneously reduce side effects, is to more narrowly target the cells causing hair loss. In the future we will have topical lotions applied to the scalp that more effectively block the DHT message from getting to hair follicle cells. Medications in pill form such as Propecia and Dutasteride affect DHT levels in the blood, which in turn affects the amount of DHT in scalp tissue, which in turn affects DHT concentrations at the cellular level in hair follicles. As a result of treating the entire system with the medication, unwanted side effects can occur in areas other than the hair follicle cells.

   In the future we will be able to better affect the DHT levels in the cells in the hair follicles, and as a result better control hair loss, and reduce unwanted side effects. Maybe medications of the future will be combined with shampoos or hair conditioners, and these products will become a common way to keep hair from falling out, just as fluoride in toothpaste is now used to help prevent teeth from falling out.

  There will also be advances in medications for treating hair loss conditions other than genetic pattern hair loss. In the future we will develop new drugs that will more powerfully signal certain cells in the hair follicles to start or remain in the anagen (growing) phase, and continue to grow hair, even when they get other signals to shut down, such as from sudden stressful events. And we will make advances in medications for treating diseases that cause both temporary and permanent hair loss.

   Diseases and conditions that cause temporary hair loss are called non-scarring alopecias by doctors. These diseases do not seem to harm or scar the hair follicle in a permanent way. The hair is lost, but it either regrows all by itself, or with the right chemical signals, can be made to regrow. Alopecia areata is a non-scarring alopecia. Some alopecia areata patients have been able to regrow hair even after years of constant hair loss. Hair loss resulting from chemotherapy, and moderate doses of radiation treatment, are also non-scarring. Hair shafts that are pulled or plucked from the follicle do not permanently damage the follicle. After being plucked, the follicle rests and recovers, and a new hair bulb is grown, and it then grows a new hair.

    Non-scarring alopecias affect the "bulb" portion of the hair follicle, which is located at the base of the follicle deep in the skin. The specialized cells in the bulb do the work of growing the hair shaft for 4 to 6 years during each hair growth cycle, but at the end of the growth cycle they seem to deteriorate as the hair follicle shrinks in size and enters the rest stage of the normal growth cycle. New hair follicle bulb cells are then produced at the beginning of the subsequent growth cycle. Future medications that effectively target or protect the cells in the bulb of the hair follicle may result in more effective treatment for alopecia areata, as well as less hair loss from stressful events and cancer treatments.

   Diseases that cause permanent hair loss are called scarring alopecias by doctors, because the disease alters or scars the hair follicle in such a way that it loses the ability to grow new hairs. Some scarring alopecias, such as lupus erythematosus and lichen planopilaris, trigger an inflammatory immune response where the body's white blood cells attack cells in the "bulge" area of the hair follicle. The bulge area is located near the middle of the hair follicle, below the sebaceous (oil) gland and near the attachment point for the arrector pili muscle (the tiny muscle that allows hairs to "stand on end").

    Androgenetic alopecia (genetic pattern hair loss) is also considered to be a scarring alopecia, as it diminishes hair follicle production over time until no new hairs are grown. New research has suggested the area of inflammation in these permanent hair loss diseases is the "bulge" portion of the hair follicle, and certain cells in the bulge area are believed to be responsible for regrowing the hair follicle at the beginning of each new growth stage. It is believed that at the beginning of each growth stage, certain cells in the bulge produce the cells in the bulb, which in turn grow new hairs. When the cells in the bulge area are sufficiently injured, the hair follicle is not able to grow a new bulb, and no new hair is produced. In the future, medications that protect the cells in the bulge area of the hair follicle will more effectively treat permanent hair loss diseases, including genetic pattern hair loss.