Medical Hair Restoration
Unusual hair loss both in men and women is caused by the alterations in the androgen metabolism. Androgen is a male hormone which has a major role to play in regulation of hair growth or hair loss. The dermal papilla is the most important structure in a hair follicle which is responsible for hair-growth. It is the dermal papilla, the cell of which divides and differentiates to give rise to a new hair follicle. The dermal papilla is in direct contact with blood capillaries in the skin to derive the nutrients for the growing hair follicle. Research has shown that dermal papilla got many receptors for androgens and there are studies which have confirmed that males have more androgenic receptors in dermal papilla of their follicles as compared to females.
The metabolism of androgen involves an enzyme called 5 alpha reductase which combines with the hormone androgen(testosterone) to form the DHT (Dihydro-testosterone). DHT is a natural metabolite of our body which is the root cause of hair loss.
Proper nutrition is critical for the maintenance of the hair. When DHT gets into the hair follicles and roots (dermal papilla), it prevents necessary proteins, vitamins and minerals from providing nourishment needed to sustain life in the hairs of those follicles. Consequently, hair follicles are reproduced at a much slower rate. This shortens their growing stage (anagen phase) and or lengthens their resting stage (telogen phase) of the follicle. DHT also causes hair follicle to shrink and get progressively smaller and finer. This process is known as miniaturization and causes the hair to ultimately fall. DHT is responsible for 95% of hair loss. Some individuals both men and women are genetically pre-disposed to produce more DHT than the normal individuals. DHT also creates a wax-like substance around the hair roots. It is this accumulation of DHT inside the hair follicles and roots which is one of the primary causes of male and female pattern hair loss.
Let us see the main drugs which are available for medical hair restoration in men and women.
Minoxidil has the distinction of the first drug being used for promoting the hair restoration. This medical hair restoration treatment drug was used earlier as an oral antihypertensive drug, but after its hypertrichosis (excessive body hair) effects were noticed, a topical solution of the drug was tested for its hair growing potential. Minoxidil was then approved as medical hair restoration treatment drug for men by the US Food and Drug Administration (FDA) in 1988 as a 2% solution, followed by 5% solution in 1997. For women, the 2% solution was approved in 1991. Though 5% solution is not approved for women, it is used as a medical hair restoration treatment by many dermatologists worldwide. Both solutions are available without a prescription in the US.
Mechanism of action
Minoxidil is thought to have a direct mitogenic effect on epidermal cells, as has been observed both in vitro in vivo. Though the mechanism of its action for causing cell proliferation is not very clear, minoxidil is thought to prevent intracellular calcium entry. Calcium normally enhances epidermal growth factors to inhibit hair growth, and Minoxidil by getting converted to minoxidil sulfate acts as a potassium channel agonist and enhances potassium ion permeability to prevent calcium ions from entering into cells.
Thought the exact action of minoxidil preventing the formation of DHT has not been shown but the drug has been shown to have a stabilizing effect on the hair loss. The result of the drug takes about few months time to be evident since it is the time which is necessary for restoring the normal growth cycle of hair fibers.
Use of Minoxidil has approved by FDA for men (Norwood II-V) and women (Ludwig I-II ) older than 18 years. It is used as a medical hair restoration treatment either for frontal or vertex scalp thinning. It brings about an increase in density which is mostly caused by conversion of miniaturized hairs into terminal hairs rather than a stimulated de novo re-growth. The hair loss becomes stabilized after continued use of drug, which takes about a year's time for the medical hair restoration treatment to show its complete results.
Hair loss restoration treatment with 0.05% betamethasone dipropionate and 5% topical minoxidil are found to be superior to minoxidil alone. Topical minoxidil is very well tolerated and adverse effects are mainly dermatologic. The most frequent adverse effect is an irritant contact dermatitis.
Though minnoxidil does not have any effect on blood pressure, it should be used with caution in patient with cardiovascular diseases. It is also contraindicated in pregnant and nursing mothers.
The drug finasteride was earlier used as treatment for prostate enlargement, under the medical name Proscar. But in 1998, it was approved by FDA for the Medical hair loss restoration in MPHL.
Mechanism of Action
Medical hair restoration treatments with Finasteride depends upon its specific action as an inhibitor of type II 5α-reductase, the intracellular enzyme that converts male hormone androgen into DHT (Dihydro Testosterone). Its action results in significant decrease in serum and tissue DHT levels in even in concentration as low as 0.2mg. Finnasteride is able to stabilize hair loss in 80% of patient with Vertex hair loss and in 70% of patients with frontal hair loss. Most of these patients are able to grow more hair or retain the ones they have. The peculiar thing about Propecia is that its effect is more pronounced in crown area than in the front. The hair that grow after the medical hair restoration treatments are better in texture and are thicker, more like the terminal hair.
The best thing about medical hair restoration treatment with the finnasteride is that it is well tolerated and has minimal side effects. Sexual dysfunction (decreased sex drive, erectile dysfunction, and decreased semen volume) are observed in about 3.8% of cases. But these side-effects subside within few months of Medical hair restoration treatments or disappear within a week's time as soon as the treatment is stopped.
There are reports which say that use of finasteride and topical minoxidil combination therapy as a Medical hair restoration treatment is of more advantage in cases of mild to moderate MPHL. Further studies are in progress. Many hair restoration doctors have already started the use of combination therapy in order to obtain better hair growth.
Anti Androgen Therapy
For women with hyperandrogonism( with increased levels of androgen) who do not respond well to minoxidil, antiandrogen therapy is another option of Medical hair restoration. In UK the most commonly used anti-androgen for women is CPA (cyproterone acetate), which is used in combination with ethinyl-estradiol.
However, in United States, where CPA is not available, the aldosterone antagonist spironolactone is the alternative choice of hair restoration doctors.
Medical hair restoration with flutamide has shown improvement as hair loss restoration treatment in women with hirsutism. For hyperandrogenic premenopausal women, flutamide is a better medical hair restoration agent than both the CPA or finestride.