Skin Problems
ALOPECIA (BALDING) - a patient's guide
Abstract
Overview:
- Hair loss is a common problem among men and it also happens to some women
- The most common form of hair loss is male pattern balding (androgenetic) and has a strong genetic component (i.e. runs in families)
- Coming to terms with hair loss is the most practical and cheapest (!) strategy, but many people find this difficult or unacceptable
- Drug treatments for men with hereditary balding include the drugs finasteride and minoxidil
- The main treatment for women is minoxidil because finasteride has little effective and can cause birth defects
- A new topical therapy for alopecia areata is still under investigation
- Hair loss may be distressing and some treatments are available as discussed in this article, but most of them are not as dramatically effective as would be desired by most sufferers
What is alopecia?
Alopecia is hair loss from the scalp which is also known as male-pattern hair loss or balding in men, or female-pattern hair loss in women.
The most common cause of hair loss is androgenetic alopecia which is thinning of the hair caused by androgens (male hormones) in those who have inherited a genetic tendency towards balding. Another cause is alopecia areata which is an autoimmune disease.
Hair loss can be an extremely distressing condition for men and women but there are now treatments available that can treat some types of hair loss.
People are born with about 100,000 hairs on the scalp. Each day about 100 hairs are shed from the scalp and about the same number enter the growth cycle. With alopecia, the hair growth cycle is shortened, and the follicles produce shorter and finer hairs.
Androgenetic alopecia:
This is the most common cause of hair loss and is due to a genetic susceptibility to balding.
Hair thinning usually begins between the ages of 12 and 40 years of age and about half the population will have experienced some degree of alopecia by the age of 50.
Hair loss is due to a shorter growth cycle of the hair; the follicles become smaller and produce shorter and finer hairs in areas prone to balding.
In male-pattern hair loss, alopecia ranges from a receding hair line, hair loss from the crown, to almost complete baldness. The presence of much finer, shorter hairs which poorly cover the scalp may be noticed.
In female-pattern hair loss, thinning is extensive and more marked on the front, sides and top of the scalp. However, most will keep some hair around the hairline although the scalp will have bald spots.
Treatment of androgenetic alopecia in men:
The aim of treatment is to increase the coverage of hair over the scalp and to prevent further hair thinning.
The best drug treatments for male hair loss is 1 mg of finasteride taken orally once a day, and minoxidil applied directly to the scalp in either 2 or 5 percent solutions twice a day. Both of these drugs increase the size of existing hairs and help prevent further hair loss. However, they still fail to restore all the hair.
Finasteride appears to be more effective than minoxidil at restoring some hair.
The best candidates for treatment are those with early balding and/or fine miniature hairs on bald patches. The drugs do not benefit men with complete baldness or those without finer hair growing in the bald regions.
Both drugs should be used for six to 12 months to improve hair growth, and continued therapy is needed to maintain existing hair.
The most effective treatment for established balding is surgical hair transplants, using plugs of hair taken from back and inserted at the top of the scalp. However, this method is expensive and there are risks of complications. An experienced surgeon is required for the operation.
Finasteride
This drug is known as a type 2 5a-reductase inhibitor and helps stop the conversion of testosterone to dihydrotestosterone.
The drug was originally developed for the treatment of benign prostatic hyperplasia (enlarged prostate), but has been registered as a treatment for male-pattern baldness in the US since 1997.
In three studies of the drug's use for alopecia, it was found that the drug significantly increased hair counts, improved scalp coverage, and increased the length, diameter and pigment of hair.
After two years of treatment with finasteride, about two thirds of men had improved scalp coverage, about one third had about the same amount of hair and about 1 percent lost hair.
Finasteride may not be effective in men over 60, and should be used with caution in those with liver disorders.
The drug should be taken once a day without food.
Side effects include:
- Loss of libido 1.8 %
- Erectile dysfunction 1.3 %
- Ejaculatory dysfunction 1.2 %
These side effects disappeared after prolonged treatment with the drug, and when the drug was stopped.
Finasteride is also known to reduce PSA levels used for prostate cancer screening. Results of PSA tests in older men should be doubled to get an accurate reading.
Minoxidil
This drug was developed to treat high blood pressure and it's not known how it can also stimulate hair growth.
This drug can be used in the treatment of areata alopecia (see below), congenital hypotrichosis, and loose anagen syndrome.
Studies show that minoxidil can increase the diameter of the hair shaft, and can halt the rapid loss of hair in some cases.
It can be used as a 2 percent or 5 percent solution and applied directly to the scalp (topically). It should be spread lightly over the scalp with your finger.
One 48-week study found men using the 5 percent solution achieved hair counts 45 percent greater than those taking the 2 percent solution and nearly five times more than men who were not being treated.
There may be a temporary increase in hair loss in the first 12 weeks of therapy. Men who want to swap minoxidil with finasteride should use minoxidil for four months after starting finasteride to prevent any hair loss that occurs from stopping minoxidil treatment.
It's believed the best results are achieved from using a combination of minoxidil and finasteride.
The main side effects from minoxidil include irritation of the scalp, itching, scaling, a rash, and rarely hypertrichosis.
Treatment of androgenetic alopecia in women:
Women are thought to be more distressed by hair loss than men, although the use of hair styling and some products can help to disguise their problem.
Women may also need to be investigated for other medical conditions if there are additional signs of an excess of male hormones.
The main treatment for female-pattern baldness is minoxidil. Finasteride is not recommended for women because of the potential for the drug to cause abnormalities in the genitalia of male fetuses.
Finasteride has also been shown to be ineffective in alopecia in postmenopausal women.
Oestrogen therapy has also been tried in women, but with little success.
Women with hair loss should be careful about the type of oral contraceptive they use to ensure they do not aggravate their problem. They should take a combined contraceptive pill with a progestin which has a low androgenic activity such as norgestimate or ethynodiol diacetate. Patients should also avoid testosterone or androgen precursors.
Minoxidil
A 2 percent minoxidil solution should be applied twice daily to dry hair. It should be applied with a dropper or spray applicator directly onto the scalp.
The 5 percent solution is not significantly more effective than the 2 percent solution in women, and there are more side effects when the 5 percent solution is used.
Side effects include irritation of the scalp, itching, scaling and a rash. Hypertrichosis is more common among women than men, with an incidence of 3 to 5 percent with the 2 percent solution.
Alopecia areata:
This is an autoimmune disease which affects about two percent of the population, and affects both sexes equally. It occurs more frequently in children and young adults.
In this condition the hair is lost in small, round patches, and it can cause total baldness.
The hair may spontaneously grow back, but regrowth may take months to years. The hair follicles remain alive so there is always the potential for hair to return.
Treatment is more effective in milder cases, and no therapy is particularly effective for total hair loss.
Treatment
The main treatment for alopecia areata is immunomodulating therapies such as glucocorticoid injections, anthralin, or glucocorticoids taken orally. Minoxidil can also be used, and a 5 percent solution is the most effective. Treatment is aimed at stimulating regrowth. It does not stop the hair loss.
Treatment should continue until the hair has grown back to an acceptable level.
Topical immunotherapy is a new treatment under investigation. It involves applying an allergen to the scalp which produces dermatitis, causing mild itching and scaling on the scalp which stimulates hair growth. How this process works is unknown at this stage.
In patients with 50 to 99 percent of hair loss, this therapy produces acceptable hair growth in 40 to 60 percent of cases. Only 25 percent of those with total hair loss respond well to the therapy.
Topical immunotherapy is currently offered at just a few centres in the US. It has also been used in Europe.