Male pattern hair loss classically presents with bitemporal hair loss that progresses to the loss of hair on the vertex, frontal, and temporal scalp. Parietal and occipital hairs are usually unaffected. It is a nonscarring form of alopecia that occurs in genetically susceptible males. The gradual involuntary loss of hair does change the natural frame hair provides around our face. The gradual loss of hair resulting in an involuntary change in appearance creates varying degree of emotional and psychological stress. Many men seek treatment for male pattern hair loss because of unhappiness with its cosmetic appearance and association with aging.
Incidence: 30% of males older than 30 years; more than half of males older than 50 years.
Age: begins after puberty.
Precipitating factors: polygenetic inherited predisposition. No diagnostic tests exist to determine the etiology and natural progression.
The precise pathophysiology remains unknown. This process is believed to result from both a polygenetic inherited susceptibility as well as androgenic stimulation. The most important androgen in this process is dihydrotestosterone.
There is a diminution in the size of affected terminal follicles that regress to become vellus follicles that eventually disappear. There is an increase in telogen hairs and a decrease in anagen hairs.
PHYSICAL EXAMINATION AND NATURAL PROGRESSION
Typically, frontal and temporal hair loss/thinning is present first. This begins in puberty and progresses over decades. The rate and extent of hair loss varies from individual to individual. Some progress to complete baldness in early 20s and others gradually thin over decades.
In males, the pattern of hair loss is characteristic suggesting no other diagnoses.
In males, no laboratory workup is typically required.
Key Consultative Questions
FDA-Approved Medical Therapy (Table 19.1)
TABLE 19.1Minoxidil and Finasteride—The Only Two FDA-Approved Medications for Male Pattern Hair Loss |Favorite Table|Download (.pdf) TABLE 19.1 Minoxidil and Finasteride—The Only Two FDA-Approved Medications for Male Pattern Hair Loss
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Mechanism of action
5-α reductase type II inhibitor blocking the conversion of testosterone to dihydrotestosterone
Key to success
Emphasize maintenance over regrowth of hair and compliance for at least 6–8 months to see benefit
Emphasize maintenance over regrowth of hair and compliance 6–8 months to see benefit
2% of men experience sexual dysfunction. Reversible within days if discontinued
No allergic reactions, blood monitoring ...