Merck Manual

Please confirm that you are not located inside the Russian Federation

honeypot link

Hairiness

(Hirsutism; Hypertrichosis)

By

Wendy S. Levinbook

, MD, Hartford Dermatology Associates

Reviewed/Revised Oct 2022
VIEW PROFESSIONAL VERSION
GET THE QUICK FACTS
Topic Resources

In men, the amount of body hair varies greatly (see also Overview of Hair Growth Overview of Hair Growth Hair originates in the hair follicles. These follicles are located in the dermis, which is the skin layer between the epidermis (the surface layer) and the fat layer (also called the subcutaneous... read more ), but very few men are concerned enough about excess hair to see a doctor. In women, the amount of hair that is considered excessive varies depending on ethnic background and culture. Usually, excess body hair is only a cosmetic and psychologic concern. However, the cause sometimes is a serious hormonal disorder, particularly in women who develop masculine characteristics (virilization).

Hairiness can be categorized as

  • Hirsutism

  • Hypertrichosis

Hirsutism is excessive growth of thick or dark body hair in women in locations that are more typical of male hair growth. Such locations include the face (on the upper lip, chin, or sideburn area), torso (around the nipples or on the chest, lower abdomen, or back), and limbs (on the shoulders or inner thighs).

Hypertrichosis is an increase in the amount of hair anywhere on the body in either sex. The excess hair may grow all over the body or only in specific locations. The hair may be fine, light-colored, and downlike or thick, dark, and long. This disorder may be present at birth or develop later.

Causes of Hairiness

Hair growth depends on the balance between male and female hormones. Male hormones stimulate the growth of thick, dark hair. Women normally produce small amounts of male hormones, and men produce small amounts of female hormones.

Hirsutism

Hirsutism usually results from high levels of male hormones (androgens, such as testosterone) or from increased sensitivity to normal levels of male hormones in the body. Testosterone stimulates hair growth in the pubic area and underarms. Dihydrotestosterone stimulates hair growth in the beard area and hair loss at the scalp.

Conditions that tip the hormonal balance in favor of male hormones can cause hirsutism. The balance may be tipped by excess production of male hormones. However, in hirsutism that runs in families (familial hirsutism), women's hair follicles simply appear to be more sensitive to normal levels of male hormones.

The most common cause of hirsutism is

There are many less common causes of hirsutism ( see Table: Some Causes and Features of Hirsutism Some Causes and Features of Hirsutism Some Causes and Features of Hirsutism ):

When hirsutism is caused by increased levels of androgens, women often have virilization.

  • The voice deepens.

  • Muscle size increases.

  • Hair is lost from the head.

  • The clitoris (the smaller female organ that corresponds to the penis) becomes larger.

  • Menstruation becomes irregular or stops completely.

  • Acne may also develop.

Hypertrichosis

Hypertrichosis is caused by disorders that do not affect the levels of male hormones.

The most common causes of hypertrichosis are

Rarely, hypertrichosis is caused by a gene mutation. In such cases, it is usually present at birth.

Evaluation of Hairiness

Doctors must determine whether the excess hair results from a disorder or is simply a cosmetic concern.

Warning signs

In women with excess body hair, certain symptoms are cause for concern:

  • Development of masculine characteristics (virilization) such as a deepened voice, increased muscle size, baldness, decreased or absent menstrual periods, and acne

  • Sudden appearance and rapid growth of excess hair (over weeks to months)

  • A growth in the abdomen or pelvis

The sudden appearance of excess hair may suggest cancer.

When to see a doctor

If warning signs are present, people should see a doctor promptly. If excess hair appears gradually without warning signs, people should see a doctor, but the visit does not need to be scheduled as quickly.

In general, women without warning signs do not need to see a doctor if they have always had excess hair, they otherwise feel well, they have regular menstrual periods and no other masculine characteristics, and have family members who also have excess hair. Such women have excess body hair because it runs in their family.

What the doctor does

Doctors first ask questions about the person's symptoms and medical history. Doctors then do a physical examination. What they find during the history and physical examination often suggests a cause and the tests that may need to be done ( see Table: Some Causes and Features of Hirsutism Some Causes and Features of Hirsutism Some Causes and Features of Hirsutism ).

Women are asked when hair began to grow excessively and where it is located, whether they have menstrual periods, and, if so, whether periods are regular. Doctors also ask whether women have had problems conceiving a child and whether any family members also have excess hair.

During the physical examination, doctors note the pattern of hair growth and look for other masculine characteristics and for other features that suggest a cause. For example, a lump felt during the pelvic examination may suggest a tumor in an ovary.

Table

Testing

Men who have no other signs of illness do not undergo further testing.

Women have blood tests to measure levels of various hormones and thus help identify the cause:

  • Testosterone

  • Dehydroepiandrosterone sulfate (DHEAS)

  • Follicle-stimulating hormone (FSH) and luteinizing hormone (LH)

  • Sometimes prolactin

Ultrasonography and/or computed tomography (CT) or magnetic resonance imaging (MRI) of the pelvis is usually done to rule out pelvic or adrenal cancer, particularly if a lump is found in the pelvis or if testosterone or DHEAS levels are high. If a pituitary disorder is suspected, MRI of the head is done.

Treatment of Hairiness

  • Treatment of the underlying condition, including stopping or changing drugs that cause hairiness

  • Bleaching or hair removal for cosmetic enhancement

  • Hormone therapy

The underlying condition is treated or corrected. For example, drugs that may cause hirsutism are stopped or changed.

Treatment for the excess hair is unnecessary unless women wish to minimize or remove it for cosmetic reasons. If excess hair growth is not related to increased levels of male hormones, physical methods are used to remove the hair. If increased levels of male hormones are the cause, hormone therapy is needed in addition to physical methods.

Physical methods

Several methods are available.

Depilation removes the part of the hair above the surface of the skin. Methods include shaving and over-the-counter creams, which may contain barium sulfate and/or calcium thioglycolate.

Epilation involves removing intact hairs with their roots. Methods to temporarily remove hairs include tweezing, plucking, waxing, and epilating devices used at home. Some methods have longer-lasting, sometimes permanent effects, but the treatments often must be repeated. These methods include electrolysis, thermolysis, and laser treatments Other methods In men, the amount of body hair varies greatly (see also Overview of Hair Growth), but very few men are concerned enough about excess hair to see a doctor. In women, the amount of hair that... read more Other methods .

Hormone therapy

Usually, hormones used to treat hirsutism must be taken for a long time because most of the disorders that cause high male hormone levels cannot be cured. These hormones include birth control pills and drugs that block the effects of male hormones, such as finasteride or spironolactone. Women who are pregnant or who could become pregnant should not take a drug that blocks male hormones because it can cause feminine characteristics to develop in a male fetus.

Gonadotropin-releasing hormone agonists (such as leuprolide) can be used if the ovaries are producing extremely high levels of male hormones, but use of these drugs requires close supervision by a gynecologist or an endocrinologist. Corticosteroids can be used to reduce levels of male hormones produced by adrenal gland tumors.

Other methods

Bleaching is an alternative to hair removal. It is inexpensive and works well when women have only a small amount of excess hair. Bleaches lighten the color of the hair, making it less noticeable. Several types of hair-bleaching products are available. Most products contain hydrogen peroxide.

Eflornithine cream, applied twice a day, slows the rate of hair growth and, with long-term use, may increase the amount of time between hair removal treatments.

Key Points

  • Excess body hair may run in families, and what is considered excessive may vary with ethnic background and culture.

  • Hirsutism, which occurs only in women, causes excess body hair to grow in a male pattern and differs from hypertrichosis, which occurs in men and women and causes excess hair to grow anywhere on the body.

  • Polycystic ovary syndrome (PCOS) is the most common cause of hirsutism.

  • If women also develop male characteristics (such as a deepened voice, increased muscle mass, scalp hair loss, or irregular or absent menstrual periods), they may have a hormone disorder that requires prompt evaluation by a doctor.

  • If excess body hair appears suddenly and grows rapidly, the cause may be cancer.

  • Treatment may include hair removal and/or hormonal therapy.

Drugs Mentioned In This Article

Generic Name Select Brand Names
Danocrine
Crinone, Endometrin , First - Progesterone MC 10, First - Progesterone MC 5, Prochieve, PROMETRIUM
Loniten, Rogaine
Dilantin, Dilantin Infatabs, Dilantin-125, Phenytek
Cequa, Gengraf , Neoral, Restasis, Sandimmune, SangCya, Verkazia, Vevye
DURYSTA, Latisse, Lumigan
IYUZEH, Xalatan, Xelpros
Anatrast, Bar Test , Baricon, Baro Cat, Barobag, Baropaque, Baropaque AC , Barosperse, Barotrast, CAT Pak , CheeTah, Digibar 90, Digital HD, E Z Cat , E Z Disk, E Z HD, E Z Paque, Enhancer, Entero H , Entrobar, Entroease, Epi-C , Esophotrast, Exacta II , E-Z-AC, E-Z-Paste, Flo-Coat , HD-200, HD-85 , Intropaste, Liqui-Coat HD, Liquid E Z Paque , Liquid Polibar , Liquid Polibar Plus, Liquid Sol-O-Pake , Medescan, Opti Up, Polibar, Prepcat, Readi Cat, Readi Cat 2, Scan-C, Sol-O-Pake, Stomach Barium Air Contrast , Stomach Barium Single Contrast, Tomocat , Tonojug Tonopaque, Tonopaque , Top Cat, Ultra R, VoLumen
Propecia, Proscar
Aldactone, CAROSPIR
CAMCEVI, Eligard, Fensolvi, Lupron, Lupron Depot, Lupron Depot-Ped, Viadur
CLEAR CARE PLUS with HydraGlyde, ESKATA, HYLAMEND
Iwilfin, Vaniqa
NOTE: This is the Consumer Version. DOCTORS: VIEW PROFESSIONAL VERSION
VIEW PROFESSIONAL VERSION
quiz link

Test your knowledge

Take a Quiz!
iOS ANDROID
iOS ANDROID
iOS ANDROID
TOP