Androgenic alopecia

Juricskay S, Telegdy E. 2000. Urinary steroids in women with androgenic alopecia. Clin Biochem 33 97. 

Topical minoxidil is effective in reversing the progressive miniaturization of scalp hairs associated with androgenic alopecia (male pattern baldness). It is a hereditary disorder due to excessive conversion of testosterone to dehydrocorticosterone in the scalp skin in genetically susceptible men. 

It is a inhibitor of 5-alpha reductase and blocks the conversion of testosterone to dehydrotesto-sterone. It prevents further hair loss in the significant proportion of men in the androgenic alopecia. 

It is used in the treatment of benign prostatic hypertrophy in the dose of 5 mg daily. In 1 mg dose it is used in the treatment of androgenic alopecia. 

Topical minoxidil (Rogaine) is effective in reversing the progressive miniaturization of terminal scalp hairs associated with androgenic alopecia. Vertex balding is more responsive to therapy than frontal balding. The mechanism of action of minoxidil on hair follicles is unknown. Chronic dosing studies have demonstrated that the effect of minoxidil is not permanent, and cessation of treatment will lead to hair loss in 4-6 months. Percutaneous absorption of minoxidil in normal scalp is minimal, but possible systemic effects on blood pressure (see Chapter 11) should be monitored in patients with cardiac disease. 

Finasteride (Propecia) is a 5K-reductase inhibitor that blocks the conversion of testosterone to dihydrotestosterone (see Chapter 40), the androgen responsible for androgenic alopecia in genetically predisposed men. Oral finasteride, 1 mg/d, promotes hair growth and prevents further hair loss in a significant proportion of men with androgenic alopecia. 

There are no data to support the use of finasteride in women with androgenic alopecia. Pregnant women should not be exposed to finasteride either by use or by handling crushed tablets because of the risk of hypospadias developing in a male fetus. 

A 43-year-old man developed impaired vision in both eyes over 3 months. Anterior subcapsular opacities were found in both eyes, necessitating cataract extraction. He had been taking finasteride 1 mg/day for 3 years to treat the early stage of androgenic alopecia. It was suspected that the drug was responsible and the treatment was therefore withdrawn. 

Finasteride (Propecia) is a 5 -reductase inhibitor that blocks the conversion of testosterone to dihydrotestosterone, the androgen responsible for androgenic alopecia in genetically predisposed men. Oral finasteride, 1 mg/d, promotes hair growth and prevents further hair loss in a significant proportion of men with androgenic alopecia. Treatment for at least 3-6 months is necessary to see increased hair growth or prevent further hair loss. Continued treatment with finasteride is necessary to sustain benefit. Reported side effects include decreased libido, ejaculation disorders, and erectile dysfunction, which resolve in most men who remain on therapy and in all men who discontinue finasteride. 

Topical minoxidil stimulates new hair growth and arrests loss of hair in androgenic alopecia. Minoxidil is poorly absorbed through the skin (less than 4%) (1), and plasma concentrations of minoxidil are far less than 10% of the mean minoxidil concentration present 2 hours after oral ingestion of 5 mg, the lowest dose for the treatment of hypertension (2). Its adverse effects after topical apph-cation are therefore usually limited to the apphcation site on the scalp. They include irritant contact dermatitis, allergic contact dermatitis, and exacerbation of seborrheic dermatitis. These effects are seen in 5.7% of patients who use a 5% solution and in 1.9% of those who use a 2% formulation (3). 

Topical minoxidil has been used to treat women with androgenic alopecia. Severe hypertrichosis of the face and the hmbs occurred in three women after 2-3 months of treatment with 5% topical minoxidil (9). The hypertrichosis disappeared from the face and arms within 1-3 months of withdrawal and from the legs after 4-5 months. 

A 24-year-old woman with androgenic alopecia became sensitized to topical minoxidil after using minoxidil 4% with retinoic acid in a propylene glycol base (13). She subsequently also became sensitized to saw palmetto (Serenoa repens), a topical herbal extract commonly promoted for the treatment of hair loss. 

A 50-year-old woman taking spironolactone for androgenic alopecia developed hepatitis with minimal cholestasis 6 weeks after starting therapy (9). After withdrawal of spironolactone, her symptoms resolved and liver function tests improved. She was not rechallenged. 

Relative contraindications to testosterone therapy include moderate to severe acne, clinical hirsutism, and androgenic alopecia. Absolute contraindications to androgen replacement include pregnancy or lactation and known or suspected androgen-dependent neoplasia. 

Hormonal therapy is useful in treating acne in women with elevated or normal serum androgens. It may also be warranted for female patients with severe seborrhea, clinically apparent androgenic alopecia, seb-orrhea/acne/hirsntism/alopecia syndrome, late-onset acne, and with proven ovarian or adrenal hyperandrogenism. ... 

Minoxidil is used topically to stimulate regrowth of hair in patients with androgenic alopecia (male pattern alopecia, hereditary alopecia, or common male baldness) or alopecia areata. Commercially available topical minoxidil preparations should be used rather than the extemporaneous topical formulations from tablets to reduce the potential of minoxidil being absorbed systemically. 

Sakr FM, Gado AM, Mohammed HR, and Adam AN. (2013). Preparation and evaluation of a multimodal minoxidil microemulsion versus minoxidil alone in the treatment of androgenic alopecia of mixed etiology A pilot study. Drug Design Development and Therapy, 1,413—423. 

Finasteride and minoxidil are used to treat androgenic alopecia. Finasteride shrinks the prostate in benign prostatic hypertrophy (BPH). Flutamidc is a testosterone receptor blocker used in prostate... 

Sexual function An American group has systematically reviewed the use of finasteride for the treatment of androgenic alopecia and found 12 published studies in 3927 patients that they regarded as eligible for inclusion [48 ]. As far as adverse reactions were concerned, moderate-quality evidence suggested an increase in erectile dysfunction (RR = 2.2 95% CI = 1.03, 4.8 NNTh=82 95% Cl = 56, 231) and a possible increase in the risk of any sexual disturbances (RR=1.4 95% Cl = 0.99,2.0). However, the risk of discontinuing treatment because of sexual adverse reactions was similar to that of placebo. The authors found moderate evidence that daily use of oral finasteride... 

Further observations performed in a subset of subjects treated with finasteride for male pattern hair loss seems, also, to indicate that sexual dysfunction as well as anxious/depressive symptomatology may occur at the end of the treatment and continue after discontinuation [26. A possible hypothesis to explain the depression symptoms after finasteride treatment might be impairment in the levels of neuroactive steroids. Therefore, neuroactive steroid levels were evaluated in paired plasma and cerebrospinal fluid samples obtained from male patients who received finasteride for the treatment of androgenic alopecia and who, after drug discontinuation, still show long-term sexual side effects as well as anxious/depressive symptomatology. 

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