Hair grows on human skin except palms and
Hair follicles New hair cells Keratin
Old Hair cells Pushed out through skin
Average Hair loss 100-150 hair strands per
Alarming Hair loss >150 hair strands per
ANAGEN-- active hair
growth that lasts between
two to six years
transitional hair growth
that lasts two to three
TELOGEN -- resting
phase that lasts about two
to three months. At the
end of the resting phase
the hair is shed and a new
hair replaces it
Involution alopecia is a natural condition in
which the hair gradually thins with age.
Alopecia areata often starts suddenly and
causes patchy hair loss in children and young
adults. This condition may result in complete
baldness (alopecia totalis). But in about 90% of
people with the condition, the hair returns
within a few years.
Alopecia universalis causes all body hair to
fall out, including the eyebrows, eyelashes, and
Trichotillomania, seen most frequently in
children, is a psychological disorder in which a
person pulls out one's own hair.
Telogen effluvium is temporary hair
thinning over the scalp that occurs because of
changes in the growth cycle of hair. A large
number of hairs enter the resting phase at the
same time, causing hair shedding and
suffers hair loss as early
as their teens or early
It's characterized by a
receding hairline and
of hair from the crown
and frontal scalp.
until their 40s or later.
It's characterized by
general thinning over
the entire scalp, with
the most extensive hair
loss at the crown.
•abnormal levels of androgens
•hormonal changes like those in
pregnancy, puberty, and
•Both male and female parents,
influence a person's predisposition
to male or female pattern baldness
•thyroid disease and iron deficiency
•. Ringworm caused by a fungal
• chemotherapy drugs used in
cancer treatment, blood
thinners, beta-adrenergic blockers
and birth control pills
•can cause temporary hair loss.
In such cases, normal hair
growth usually returns once the
es, and X-
•cause alopecia areata
•In most people with alopecia
areata, the hair grows back
• shampooing too often, perms,
bleaching, and dyeing hair
contribute to overall hair thinning
• severe damage to the hair causes
permanent bald patches.
Finasteride (brand names Proscar and Propecia
by Merck, among other generic names) is a
synthetic drug approved by the FDA for the
treatment of benign prostatic hyperplasia (BPH)
and male pattern baldness (MPB).
It is a type II 5α-reductase inhibitor. 5α-reductase is an enzyme
that converts testosterone to dihydrotestosterone (DHT).
In clinical studies, finasteride, like minoxidil, was shown to work
on both the crown area and the hairline, but is most successful in
the crown area.
Gynecomastia, erectile dysfunction and depression, are some
Dutasteride (trademark name Avodart,
manufactured by GlaxoSmithKline) is
approved for the treatment of benign
prostatic hyperplasia and used off label for
It is a dual 5-a reductase inhibitor that inhibits conversion
of testosterone to dihydrotestosterone (DHT). The drug
inhibits all three isoforms of 5-alpha reductase, whereas
finasteride only inhibits type II and III.
Alfatradiol is a topical 5α-reductase inhibitor that has been
shown to slow progression of hair loss in women. It is
marketed as Avixis, ELL Cranell Alpha and Pantostin.
Minoxidil is an antihypertensive vasodilator medication. It also
slows or stops hair loss and promotes hair regrowth. Now off-
patent, it is available over-the-counter for the treatment of
Minoxidil is also a vasodilator. Hypothetically, by widening blood
vessels and opening potassium channels, it allows more oxygen,
blood, and nutrients to the follicle. This may cause follicles in the
telogen phase to shed, which are then replaced by thicker hairs in
a new anagen phase.
Minoxidil needs to be applied once or the recommended twice
daily, and may be used indefinitely for continued support of
existing hair follicles and hair regrowth. To achieve maximum
effect, the solution should be in contact with the scalp for at least 4
hours before allowing hair to get wet.
. Minoxidil stimulates hair follicles and growth, but does not
reduce DHT or the enzyme responsible for its accumulation
around the hair follicle, 5-alpha reductase, which is the primary
mediator of male pattern baldness.
Treatments usually include a 5% concentration solution that is
designed for men, and a 2% concentration solution for women.
Common side effects of minoxidil include burning or irritation
of the eye, itching, redness or irritation at the treated area, as
well as unwanted hair growth elsewhere on the body
It is marketed under many trade names, including Avacor
Physician's Formulation, Loniten (oral), Mintop, Amexidil,
Rogaine, Spectral.DNC, and Vanarex
Ketoconazole is a topical anti-fungal agent. As an imidazole,
Ketoconazole is effective for the treatment of dermatitis and
dandruff. It is also an anti-androgen, and may improve hair
Spironolactone is a possible selective androgen receptor
modulator, and both reduces adrenal androgen production
and exerts competitive blockade on androgen receptors in
target tissues. It can be administered topically or
systemically. Due to its feminizing side effects and risk of
infertility in men; it is used more often in female androgenic
Flutamide has more anti-androgenic activity than
spironolactone, and is also referred to as chemical
castration. It can cause marked reduction in libido and
estrogenic side effects including gynecomastia, lipid
profile changes, and emotional lability, although when
used in women it can be associated with increased
positive affect. There is a significant incidence of hepatic
dysfunction with the medication in women . Like
spironolactone, it is more often used clinically in female
Hair transplantation is a surgical
technique that moves individual hair
follicles from a part of the body called the
donor site' to bald or balding part of the
body known as the 'recipient site'.
It is primarily used to treat male pattern
In this condition, grafts containing hair follicles that are
genetically resistant to balding are transplanted to bald
More recently, bioengineered hair follicles have been
successfully transplanted to create histologically normal hair follicles.
Chemotherapy induced hair loss occurs by a non-
androgenic mechanism, and can manifests as
It is usually associated with systemic treatment
due to the high mitotic rate of hair follicles, and
more reversible than androgenic hair loss, although
permanent cases can occur.
It is usually reversible, with prophylactic measures including
scalp cooling, and temporary interval cosmeses such as wigs
and head garments.
It can be self-contained and resolve without therapy, although there
are relapsing and remitting forms of the illness.
In distinction to androgenic hair loss, pulsed corticosteroid therapy
has been found effective over the long term in its treatment.
Topical calcipotriol, a vitamin D derivative, has been used
successfully in treatment of areata.
Telogen effluvium is hair thinning or shedding from early entry of
the follicle into telogen.
Most cases are self-limited and resolve on their own, although zinc
has shown some effectiveness in treatment.