No, although some cases can run in families.

Hirsutism can be caused by an increased androgen (male hormone) production, increased skin sensitivity to androgens, or both. Androgens are often thought of as exclusively ‘male hormones’ but, in fact, both men and women produce them, although men usually in greater amounts than women.

In premenopausal women, the most common cause of hirsutism is polycystic ovary syndrome (PCOS). However, in 5-20% of affected women no apparent underlying cause is found. It is common for women to develop more facial or body hair gradually as they get older, especially after the menopause.

Rarely, hirsutism can be caused by medications such as steroids or hormonal disorders. Extremely rarely, hirsutism can be caused by tumours that secrete androgens. In such cases the hirsutism will be severe and appear over a few years.

The dermatologist may request some hormone tests, possibly an ultrasound of the pelvis (to investigate the potential diagnosis of PCOS) and may refer you to an endocrinologist (specialist in hormonal disorders).

It is important to see a doctor if hirsutism is associated with any of the following: 

• Developing quickly (over 1-2 years), or before puberty.
• Accompanied by menstrual problems.
• Associated with features suggesting an increase in androgens such as thinning of the scalp hair, baldness, or deepening of the voice.
• Accompanied by obesity or diabetes.

In the rare cases where there is an underlying hormonal disorder, the doctor may suggest treating this first.

Treatments for hirsutism where there is no underlying cause or in association with PCOS include:

• Shaving. Some people believe that shaving encourages more hair growth, but this is not true. However, the stubble that follows regrowth may be undesirable. Frequent shaving can irritate your skin.
• Waxing is effective for some people, but can irritate the skin and should be used with caution on the face. Pseudofolliculitis, also known as ‘shaving bumps’, or ‘razor bumps’, may occur with both shaving and waxing and is caused by hairs being trapped beneath the skin surface which become inflamed. It may result in discolouration of the skin or scarring.
• Depilatories (creams that remove hair) chemically dissolve hair shafts thereby leaving no stubble, but may also irritate the skin. Before using depilatories, a skin test should be carried out to check they can tolerated. Please follow the manufacturer’s instructions for testing and product applications.
• Bleaching creams are designed to make the dark hairs pale. Such creams can irritate the skin and may temporarily lighten darker skin tones.

• Electrolysis. An electrical current is passed into a hair follicle through a needle. The aim is to destroy the hair root permanently. Multiple treatments are often needed. The procedure may be painful and the use of local anaesthetic cream on the skin prior to treatment might be helpful. It is a relatively expensive, time-consuming treatment and is not normally available on the NHS. Before having electrolysis, check that the operator is qualified and registered with the British Institute and Association of Electrolysis, and that the practitioner uses new, disposable (not simply re-sterilised) needles. Home electrolysis machines are not recommended. Scarring is a potential side-effect of this treatment.
• Laser and intense pulsed light (IPL) treatments aim to destroy the hair root permanently. Laser treatment and IPL are expensive and are not normally available on the NHS. Several treatments are given over a period of months and should be performed by a practitioner who is properly qualified. Please check that they are registered with the Care Quality Commission or British Medical Laser Association. Possible side-effects include redness, discolouration of the skin and scarring. Adherence to the treatment plan provided by the practitioner is important and may include no sunbathing, no use of sunless tanning lotions and sprays or hair removal with the exception of shaving or trimming of hair in the area to be treated. 

• Eflornithine cream works by slowing hair growth. Its use has been studied on the face and adjacent areas such as under the chin, and may be used in conjunction with other hair removal methods. Eflornithine cream may take at least 4 to 8 weeks of regular use to notice a beneficial effect and continued treatment is needed to maintain the effect. Side-effects include burning or stinging of the skin, folliculitis (inflammation of hair follicles) and acne. It is not a depilatory cream.
• Oral contraceptive pills. The combined oral contraceptive pill reduces the amount of circulating free androgens and may help to reduce hirsutism, especially those that have a progestin component that is less androgenic or are combined with an anti-androgen such as cyproterone acetate or drospirenone. It may take 6 to 12 months to notice an effect. It is important to discuss the choice of contraceptive pills with a doctor as there are many different types available.
• Anti-androgens. The doctor may prescribe these to block the action of the androgens that can cause hirsutism. These medicines include finasteride, cyproterone acetate or spironolactone. They may take several months to have an effect and the hirsutism tends to return when the medicine is stopped. They may be associated with side-effects such as loss of libido, tender breasts and menstrual irregularities. They can harm an unborn male baby and female patients of child-bearing potential taking these medicines must use effective contraception. Therefore, these medicines are often used together with the oral contraceptive pill or with other forms of contraception such as the intrauterine device (coil). They are not formally approved for the treatment of hirsutism in the UK and may be available off-licence with informed consent.
• Other medicines. Insulin sensitisers, including metformin and pioglitazone, are widely used in PCOS which is associated with hirsutism. The evidence for their use in the treatment of hirsutism has been unconvincing and may be less effective than the oral contraceptive pill and anti-androgens.

Images DermNetNZ.