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HAIR LOSS & ALOPECIA (BALDING) - a patient's guide
Editorial Team
Hair Loss Overview
Hair loss is a common problem and primarily affects men, but can also
affect women.
The most common form of hair loss is male pattern balding (androgenetic)
and has a strong genetic component (ie. 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 effect 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.
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