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Hair Loss

Hair Loss
Causes of Hair Loss
Treatments for Hair Loss

Causes of Hair Loss

      Hair growth follows two stages. Approximately 90% of hair growth on the scalp follows a 4-5 year growth stage. The remaining 10% follows a 2-3 month resting stage before it is shed from the scalp. Once the hair is shed, new hair growth occurs at a rate of about one half inch per month.

Hair loss can occur when the rate at which hair is shed is greater than the rate of hair re growth, when hair is shed in patches or when hair re growth results in thinner hair than what was shed.

Many people incorrectly believe that androgenic alopecia only happens in men. Women too can experience this type of hair loss. The cause of androgenic alopecia is heredity. Heredity affects many aspects of androgenic alopecia, including the rate of hair loss, the pattern and extent of hair loss and the age at which hair loss begins. A history of baldness on either the male or female side of the family increases the risk of balding.

Alopecia areata is an autoimmune disease, the causes of which are still unknown. Heredity can plan a role, making the likelihood of developing the disease greater when a family history of the disease is present. Alopecia areata is usually temporary, but it can take many years for the hair to grow back.

There are several causes of temporary hair loss, outside of heredity. These include:

- Medications (exs. high blood pressure, depression, arthritis, gout)
- Medical Treatments (exs. chemotherapy/radiation, surgery, flu treatments)
- Diseases (exs. diabetes, thyroid disorders, lupus)
- Childbirth
- Hair Products (ex. hair dyes, bleaching, perming)
- Scalp Infections (ex. ringworm)

The American Academy of Dermatology offers excellent resources and articles concerning all types of hair loss, treatments and causes. For information about treating hair loss with Propecia, read about Propecia & Merck & Co., Inc.

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