Androgenetic alopecia (AGA), also known as male or female pattern baldness, is a widespread form of hair loss with a genetic basis. The condition arises from a genetically determined sensitivity of hair follicles to the hormone dihydrotestosterone (DHT). In individuals with this predisposition, DHT binds to receptors in scalp follicles, causing them to shrink in a process called follicular miniaturization. This progressive shrinking shortens the hair’s life cycle, resulting in finer strands that eventually cease to grow. The condition affects up to 80% of men and 50% of women to some degree.
Over-the-Counter and Topical Solutions
For accessible, non-prescription options, topical solutions applied directly to the scalp are a primary choice. The most prominent of these is Minoxidil, recognized under brand names like Rogaine. Minoxidil functions as a vasodilator, meaning it widens blood vessels. This action is believed to improve the flow of blood, oxygen, and nutrients to the hair follicles, which can help reactivate dormant follicles and reverse their miniaturization.
Minoxidil is also thought to prolong the anagen, or growth phase, of the hair cycle, leading to longer and thicker hair strands over time. It is available in 2% and 5% solutions or foams and must be applied consistently to the scalp once or twice daily. Results, such as reduced shedding and new growth, become apparent after several months of continuous application. Its effects are dependent on ongoing use; if treatment is stopped, the newly regrown hair is typically lost within a few months.
Another topical product used to address hair loss is shampoo containing ketoconazole. Primarily an antifungal agent for dandruff, ketoconazole has been observed to have a mild anti-androgenic effect. It may interfere with the pathways that produce DHT on the scalp, reducing the hormone’s impact on sensitive follicles. These shampoos can also improve overall scalp health by reducing inflammation sometimes associated with AGA.
Prescription Oral Medications
For a more systemic approach, physicians may prescribe oral medications that work internally to counteract the hormonal drivers of androgenetic alopecia. The most established for men is Finasteride, a 5-alpha reductase inhibitor. This enzyme is responsible for converting testosterone into dihydrotestosterone (DHT). By blocking the Type II form of this enzyme, Finasteride can decrease DHT levels in the scalp by up to 70%, reducing the hormonal signal that causes follicular miniaturization.
Finasteride can effectively slow the progression of hair loss and, in many cases, stimulate new growth, particularly at the crown. A more potent oral medication, Dutasteride, is sometimes prescribed off-label for male pattern hair loss. Dutasteride inhibits both Type I and Type II forms of the 5-alpha reductase enzyme, leading to a more substantial reduction in DHT levels. This broader action may make it more effective for some individuals who did not respond to Finasteride.
Treatment for female pattern hair loss often involves a different hormonal approach, as Finasteride is not approved for women due to potential risks during pregnancy. A common off-label prescription for women is Spironolactone, a potassium-sparing diuretic. Spironolactone functions as an androgen receptor blocker, competing with DHT at the hair follicle and reducing androgen production. This can help slow down hair thinning and encourage regrowth in women.
Therapeutic Procedures and Devices
Beyond daily medications, several therapeutic procedures and devices offer non-surgical avenues for addressing hair loss, such as Low-Level Laser Therapy (LLLT). LLLT is a non-invasive treatment that uses red or near-infrared light to stimulate follicular activity. The light energy is absorbed by cells in the follicles, boosting their metabolic rate and enhancing blood circulation. LLLT is available through in-office equipment or at-home devices like caps, combs, and headbands.
Another clinically performed procedure is Platelet-Rich Plasma (PRP) therapy. This treatment begins with drawing a patient’s blood, which is then spun in a centrifuge to concentrate the platelets. This platelet-rich plasma, containing a high concentration of growth factors, is then injected into thinning areas of the scalp. These growth factors are believed to rejuvenate shrinking follicles and stimulate dormant ones back into a growth phase. A course involves several sessions spaced four to six weeks apart.
Microneedling is a procedure that can be used on its own or to complement other treatments. It involves using a device with fine needles to create microscopic punctures in the scalp. This controlled injury triggers the body’s wound-healing response, which releases growth factors and stimulates collagen production. When used with topical solutions like Minoxidil, microneedling has been shown to enhance the absorption of the medication, allowing it to work more effectively.
Surgical Hair Restoration
For those seeking a more permanent change, surgical hair restoration offers a definitive solution. The principle of hair transplant surgery is the relocation of healthy, genetically robust hair follicles from a donor area to thinning regions of the scalp. These donor follicles, harvested from the back and sides of the head, are naturally resistant to the effects of DHT and retain this characteristic when moved.
Two primary surgical techniques are Follicular Unit Transplantation (FUT) and Follicular Unit Extraction (FUE). The FUT method involves surgically removing a linear strip of scalp tissue from the donor area. This strip is then dissected into individual follicular units of one to four hairs, which are implanted into the recipient sites. This technique allows for a large number of grafts to be harvested in a single session but leaves a linear scar.
The FUE technique is a more minimally invasive approach. In an FUE procedure, a surgeon extracts individual follicular units directly from the scalp one by one using a micro-punch tool. This method avoids a linear incision, leaving tiny, dot-like scars that are less noticeable. While FUE may be more time-consuming, its quicker recovery and minimal scarring have made it an increasingly popular choice.