An over-stimulation of hair follicles by androgenic hormones results clinically in hirsutism. It may take place in the setting of elevated levels of androgens; or even with normal levels of circulating androgens, in the setting of increased follicular sensitivity to male hormones, or in the setting of declining estrogen levels (menopause).
The first and most important step is a thorough clinical history and physical examination; when an underlying hormonal disorder is suspected, laboratory investigations will be ordered.
Therapeutic options may include:
- Systemic Therapies such as oral contraceptives and antiandrogens (Spironolactone, Cyproterone acetate)
- Topical Therapies like Eflornithine hydrochloride cream
- Temporary removal includes plucking, waxing, shaving and chemical depilatory agents.
- Permanent removal using laser and intense pulse light (IPL) or electrolysis.
Hair loss in Men
About 90% of scalp hair loss in men is hereditary, and is attributable to androgenic or male-pattern baldness. This is caused by a genetic sensitivity of the developing hair follicle to DHT (dihydrotestosterone)- a metabolite of testosterone.
DHT causes minaturization of the hair follicles, causing the follicle to grow baby (vellus) hair, and eventually resulting in a receding hairline. Typically, the recession commences at the temples and front of the scalp, progressing to involve the crown, leaving a rim of hair around the edge and back of the scalp, which may, in time, also disappear.( see Norwood scale for severity of hair loss)
DHT is produced from testosterone by the action of an enzyme called 5-alpha -reductase; the action of this enzyme can be blocked by 2 drugs- finasteride and dutasteride– thus slowing, and even reversing, the hair loss.(These drugs are also used to shrink enlarged prostates. There are 2 types of receptors for 5 alpha-reductase – type 2, which is mostly located in the prostate, and type 1 , which is the primary receptor on the scalp. Dutasteride is about 100 times more potent than Finasteride in inhibiting type 1 alpha reductase, and is also absorbed through the skin, which potentially allows it to be administered directly on the scalp (an off label use). Side effects of both drugs include decreased libido, and a reduction in PSA levels . Both drugs need to be used for a minimum of 6 months to see noticeable improvement in scalp hair regrowth.
Other drugs used for scalp hair loss are Minoxidil ( 2- 5% solution)- a low-dose topical form of an anti-hypertensive drug. The mechanism of action of minoxidil in preventing hair loss is not well understood, although it appears to shorten the shedding (telogen) phase and increase the growth (anagen)phase of the follicle . It appears to be much more effective for women.
Other Non- surgical modalities of treatment:
The use of Low-level (cold) lasers for alopecia has been extensively studied, and appears to be promising. Low-level laser has a stimulating effect on intracellular metabolism, and improves micro-circulation to the scalp. Hair gets thicker, longer and denser. Some studies have demonstrated hair regrowth in up to 85% of users at 6 months. Hand-held devices are available on the internet, Men and women can benefit from this treatment; the best responders being those with androgenic alopecia in the early stages of hair loss. It can also be used as an adjunct for those patients already on medication
Selphyl (platelet-rich fibrin matrix) has also been proposed as a treatment for alopecia; the growth factors attached to platelets may have a stimulating effect on developing follicles, and improve microcirculation to the scalp.
Drug-induced hair loss:
Many prescription drugs may cause hair loss; some anti-coagulants, acne medications, lipid-lowering drugs, anti-inflammatories, anti epileptics, anti-depressants, beta-blockers, steroids, acid-suppressing drugs, birth control pills (women) etc. DO NOT STOP ANY PRESCRIPTION DRUGS WITHOUT FIRST CONSULTING YOUR DOCTOR!!!!!
Hair loss in Women
Androgenetic hair loss is only one of several factors to be considered when teasing out the causes of hair loss in women. The pattern of hair loss is different; usually presenting as a diffuse thinning of scalp hair, eventually progressing to visible hair loss in the centre of the scalp around where the hair naturally parts. less often frontal recession of the hairline. (Ludwig or Savin Scale for degree of severity)
In diagnosing the cause, one should consider traction ( mechanical pulling on the hair – elastic bands, tight braids; perms; nervous habits such as twisting the hair- trichotillomania); the effects of hair dyes and other products, as well as considering side effects of medications, nutritional deficiencies (esp. Iron deficiency) stress, and hormonal conditions ( particularly hypothyroidism, polycystic ovarian syndrome).
Other causes of alopecia:
- Alopecia areata– patchy hair loss- on scalp, eyebrows,- an auto-immune disorder, this is treated by topical application of , or local injections of, steroids, or immune-modulating drugs
- Scarring alopecia– can be the result of traction, lupus, scleroderma, or localized fungal infections or folliculitis.
- Telogen effluvium– when a large proportion of scalp hair follicles shift into the shedding phase-causes could be hormonal, nutritional, medication related, following a systemic illness, or postpartum (can last 6-12 months, will recover spontaneously)
Approach towards female hair loss:
History– recent illness, surgery, pregnancy or stress
Medications being taken
Family history – of androgenetic hair loss
Traction or harmful processes to hair
Localized plaques, scarring, inflammation- swabs, scrapings, biopsy
Hormonal causes: thyroid, other hormones -DHEA, testosterone, prolactin, declining estrogen levels
Nutritional causes: Low Iron – primary cause for hair loss in a lot of cases; other nutritional deficiencies – Zinc, Chromium, B6, low protein diets, anorexia..
Auto-immune disorders: e.g. lupus, alopecia areata
Non – Surgical Treatments
Apart from correcting any obvious hormonal (thyroid) or nutritional factors (Iron deficiency), and eliminating medications that could be causing hair loss, the first step would be using
- Topical Minoxidil in a 5% solution twice daily;
- the use of androgen blockers ( e.g. Spironolactone ) which inhibit the effect of androgens on hair follicle receptors;
- in women of perimenopausal age, Finasteride or Dutasteride could be tried on the principle that declining estrogen and a relative excess, or excessive sensitivity to, androgens may be at play- but these drugs can have harmful effects on developing foetus and so should be avoided in women of childbearing potential.
- Young women with PCOD who have androgen excess – (acne, oily skin facial hirsuitism)- may benefit from an anti-androgen BCP – such as Diane 35 (contains the anti-androgen cypoterone acetate), Yaz or Yasmin (contain the progestogen drospirenone) – but should note that these medications have been associated with an increased incidence of thromboembolic disease (stroke, blood clots).
Low-level laser therapy is a good option.
Scalp Mesotherapy (see Injectables: Mesotherapy) or treatment with Selphyl PRFM may be tried as adjunctive therapies.