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Hair loss

Contents of this page:

Illustrations

Hair follicle
Hair follicle
Ringworm, tinea capitis - close-up
Ringworm, tinea capitis - close-up
Alopecia areata with pustules
Alopecia areata with pustules
Alopecia totalis - back view of the head
Alopecia totalis - back view of the head
Alopecia totalis - front view of the head
Alopecia totalis - front view of the head
Alopecia, under treatment
Alopecia, under treatment
Trichotillomania - top of the head
Trichotillomania - top of the head
Folliculitis, decalvans on the scalp
Folliculitis, decalvans on the scalp

Alternative Names    Return to top

Loss of hair; Alopecia; Baldness; Telogen effluvium

Definition    Return to top

Partial or complete loss of hair is called alopecia.

Considerations    Return to top

Hair loss usually develops gradually and may be patchy or all over (diffuse). You lose roughly 100 hairs from your head every day. The average scalp contains about 100,000 hairs.

Each individual hair survives for an average of 4 1/2 years, during which time it grows about 1/2 inch a month. Usually in its 5th year, the hair falls out and is replaced within 6 months by a new one. Genetic baldness is caused by the body's failure to produce new hairs and not by excessive hair loss.

Both men and women tend to lose hair thickness and amount as they age. Baldness is not usually caused by a disease. It is related to aging, heredity, and testosterone. Inherited or "pattern baldness" affects many more men than women. About 25% of men begin to bald by the time they are 30 years old, and about two-thirds are either bald or have a balding pattern by age 60.

Causes    Return to top

A sudden physical or emotional stress may cause one-half to three-quarters of the hair throughout your scalp to shed (called Telogen effluvium). You will notice hair coming out in handfuls while you shampoo, comb, or run your hands through your hair. You may not notice this for weeks to months after the episode of stress. The hair shedding will decrease over 6 - 8 months.

Cause of this type of hair loss are:

Some women ages 30 - 60 may notice a thinning of the hair that affects the entire scalp. The hair loss may be heavier at first, and then gradually slow or stop. There is no known cause for this type of hair loss.

Other possible causes of hair loss, especially if it is in an unusual pattern, include:

Home Care    Return to top

Hair loss from menopause or childbirth often returns to normal 6 months to 2 years later.

For hair loss due to illness (such as fever), radiation therapy, medication use, or other causes, no treatment is necessary. The hair will usually grow back when the illness has ended or the therapy is finished. You may want to wear a wig, hat, or other covering until the hair grows back.

Hair weaves, hair pieces, or changes of hair style may disguise hair loss. This is generally the least expensive and safest approach to hair loss. Hair pieces should not be sutured to the scalp because of the risk of scars and infection.

When to Contact a Medical Professional    Return to top

Call your doctor if:

What to Expect at Your Office Visit    Return to top

A careful medical history and examination of the hair and scalp are usually enough to diagnose the cause of your hair loss.

Your doctor will ask detailed questions such as:

Tests that may be performed (but are rarely needed) include:

Ringworm on the scalp may require the use of an oral drug, such as griseofulvin. Creams and lotions applied to the affected area may not get into the hair follicles to kill the fungus.

See also:

References    Return to top

Hair diseases. In: Habif TP, ed. Clinical Dermatology. 4th ed. St. Louis, Mo: Mosby; 2004:chap 24.

Diseases of the hair. In: Rakel P, ed. Conn’s Current Therapy 2008. 57th ed. Philadelphia, Pa: WB Saunders; 2008: chap 195.

Update Date: 5/7/2009

Updated by: Michael Lehrer, MD, Department of Dermatology, University of Pennsylvania Medical Center, Philadelphia, Pa. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

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The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. Copyright 1997-2009, A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.