Monday, June 3, 2013

Alopecia - Concepts, Information, Causes, Prevention, and Treatment Options


3.-Types of alopecia


The term alopecia defines hair loss. It can be triggered by various causes. The life cycle of hair consists of three phases: the growth phase or anagen phase lasting 2 to 6 years, the intermediate phase or cagagen phase with a duration of 2 to 3 weeks, and lastly the dislodgement or falling phase, with a duration of three months. During this last phase it is normal for between 50 and 100 hairs to fall out a day. Baldness is generated when the transition phase (catagen phase) exceeds the growth phase (Anagen phase).

Causes Some of the factors that influence hair loss are:

o Seasons: Spring and autumn are the most common seasons for hair loss.
o Oral contraceptives: Hair loss can be accelerated by the effects of the male hormone contained in some contraceptives.
o Lack of iron: This problem is more common in women especially if they have heavy or long periods.
o Diet: vegetarians, people who have a low protein diet and patients with anorexia nervosa may be protein deficient. As a result, in about three months time there can be a massive loss of hair.
o Postpartum: after childbirth some hair may enter the resting phase and begin to fall out.
o Stress and illness: you can begin to lose hair after a stressful situation. A high fever, severe infections or chronic diseases can also cause hair loss.
o Medications: Some drugs used in chemotherapy cause hair to stop cell division. This can cause loss of up to 90% of hair, but in most cases the hair will begin to re-grow once the treatment ends.
o Heredity: baldness may be genetic.
o Burns and traumas.

Types of Alopecia

We can distinguish between different types of alopecia. The most common types include: Scar less Alopecia: -Androgenetic alopecia: Also known as common alopecia as it is the most frequent form of alopecia. Hair loss starts from age 18, and is apparent between the ages of 25 and 30. In this type of hair loss, lost hair is replaced by increasingly thinner and shorter hair follicles, and in some cases even transparent hair. This type of alopecia is inherited from both father and mother. In these cases there is an abundance of dihydrotestosterone (DHT), a male hormone within the hair follicle. DHT causes the atrophy of the follicle, reducing the growth cycle. Although the follicle is technically alive, each time it grows back even smaller. Some follicles just die, but most are smaller, and fluffier.

As the Anagen phase remains very short, more hair begins to fall out, gradually thinning until it becomes so fine that it can not resist daily combing. Baldness turns a long, thick, pigmented hair into thin, clear and short hair. This type of hair loss has a very distinctive pattern in men (male pattern baldness) affecting primarily the area above the temples with a receding hair line, as well as thinning hair on crown of the head. In women, this type of alopecia usually starts between age 20 and 30, with a gradual thinning of hair all over the head, hair miniaturization, and a no receding of the hair line. About 2 out of every 3 men experience a significant negative impact on their self esteem due to alopecia.

-Alopecia diffusa: Characterized by thinning hair (acute or chronic) and is due to a cycle interruption of the follicular anagen phase or telogen phase. In this type of alopecia only the hair follicles of the scalp are affected. There is no change in hair follicles from other parts of the body. It affects both men and women.

Telogen Effluvium: Consists of sudden and widespread hair loss due to causes such as stress, fever, abortion, endocrinological diseases, infectious diseases, surgery, etc... It is the most common form of postpartum alopecia because after birth, much of the follicles enter the Telogen phase (30%) and in the end fall out. Normally appears to 2-3 months after delivery and returns spontaneously in a few months.

-Alopecia Areata: Characterized by a hair loss occurring in round smooth patches, that takes place in one or more limited areas of the scalp or body. Its origin is unclear, but more and more studies suggest that alopecia areata is an autoimmune disease in which the body produces antibodies against a part of the hair follicle. Stressful situations can also cause the appearance of this type of alopecia. Can occur in both men and women, but most often affects youth.

-Traumatic Alopecia: Produced by different physical traumas. This type of hair loss can be caused by the individual person (Trichotillomania) or pull or tension caused by tight hairstyles like braids, bows, etc ... Trichotillomania: Consists of compulsive hair pulling. Is often set before age 17, and may be due to a need to draw the attention or a nervous tic.

Scarring alopecia

-Infectious Alopecia: . Mycosis (kerion, candidiasis, favus) . Bacterial (syphilis, leprosy, necrotic acne) . Viral (herpes, chickenpox). Protozoal (Leishmaniasis)

- Traumatic Alopecia: . Traffic accidents . Ionizing Radiation (Therapeutic) . Thermal burns or frostbite.

- Chronic Inflammatory Dermatosis Alopecia: . Discoid Lupus Erythematosus . Lichen Planus Pilaris . Folliculitis Decalvans


Alopecia treatments that stand out are: -Minoxidil. An oral medication used to control high blood pressure. Patients taking Minoxidil showed noticeable hair growth. Therefore, for over 10 years it has been used is used in topical solutions to the control hair loss. Today it is one of the most effective treatments of androgenetic alopecia and other types of hair loss, including alopecia areata patches, total scalp hair loss, or universal hair loss. Comment: Minoxidil solutions make the hair oilier, so the head should be washed more frequently and with a proper shampoo. It is advised to wash the hair 1-2 times a week. Some patients may experience transitional itching and slight flaking on treatment areas; this should not be a reason to stop the treatment. Contraindications: Allergy to Minoxidil or its transmitter (propylene). Pregnancy.

- Antiandrogens. Reduce the male hormone (DHT) that causes baldness. DHT is an androgen (male hormone) competing for a place in the hair follicle receptors. If follicle receptors are occupied by other agents, DHT cannot enter the hair follicle and therefore does not induce aggressive action. The problem is that by blocking DHT, elsewhere in the body signs of feminization may begin to show in men. In contrast, in women this block is less problematic.

Within this group we find Finasteride, a type II 5-alpha reductasa inhibitor. This makes the conversion of testosterone to dihydrotestosterone (DHT). The type II 5-alpha reductase is located mainly in the follicles of the scalp and the urogenital tract. The inhibition of the type II enzyme prevents the destructive action of DHT in hair follicles.

- Surgical techniques: include hair transplants, grafts, implants, etc ...


Hereditary hair loss is not curable, but it is controllable, and the sooner be treated the better. Currently there is not a perfect treatment for androgenetic alopecia, but there are drugs that stop hair loss and prolong the life of hair follicles. We must consider the present and future hair treatments because hair needs living hair follicles. With baldness follicles are miniaturized and die after 5-10 years. With any treatment you will get better results with more follicles that remain alive. Many other hair problems are temporary and can be treated by dietary measures and other measures. In these cases, good dietary habits as well as eating supplements of vitamins, minerals and antioxidants help to stop hair loss and regain normal growth after a few months. For more information about hair loss, consult your dermatologist, because skin diseases include diseases of the hair and nails. Do not be influenced by advertisements for "hair tonic" or by hairdressing specialists.

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