Hair loss overview

Why does hair loss occur?

There are several reasons for hair loss, but by far the most common cause in men is inherited male pattern baldness, also called androgenetic alopecia, which affects more than 95 per cent of men.

This type of baldness is more common in men of Caucasian (European) and Australian Aboriginal backgrounds than, for example, in men of Asian or African background. It is characterised by hair loss that occurs in a distinct pattern. Usually the hair loss begins at the forehead with a receding hair line, then a bald patch may develop at the back or crown of the head. Ultimately, all hair can be lost from the top of the head.

progression of male pattern baldness

The normal hair cycle

During the normal hair cycle, 90 per cent of the approximately 150,000 hairs on a man’s scalp are in a growth phase, and the remaining 10 per cent are in a resting phase, with up to 100 hairs shed each day, only to be replaced by the growth of new hairs.

So that all hairs on the scalp are not shed at once, each hair follicle (the group of specialised cells in the scalp that produce and support each hair) follows its own cycle, progressing from the growth phase, which in men averages 2 to 3 years, to the resting phase lasting approximately 3 months, during which there is no growth in the hair. After the resting phase the hair falls out.

Male pattern baldness

In male pattern baldness, the growth phase of each hair gradually becomes shorter, whereas the resting phase becomes longer. Eventually the hairs that are growing become so short that they barely emerge from their hair follicle. There is also an increasing lag time between the end of the resting phase and the next growth phase, also resulting in fewer hairs emerging.

The changes that occur in male pattern baldness are strongly influenced by inheritance or your genes, and by an increased sensitivity of the hair follicles to male hormones. In particular, male pattern baldness is thought to be due to the breakdown of the male hormone testosterone to dihydrotestosterone within the hair follicle. However, it is your genes that will determine whether or not you will develop this type of hair loss and at what age it starts, as well as how extensive it will be and the pattern that the hair loss will follow.

Some other causes of hair loss

Medical conditions and medications

Hair loss can also occur after a severe illness accompanied by a high fever, major surgery, long-term illness, rapid weight loss, anaemia, thyroid disease, chemotherapy that is used to treat cancer, sudden shock such as a bereavement, and with the use of certain medications, for example, some of those used to control high cholesterol or high blood pressure.

Alopecia areata

This is an immune system disorder in which scalp hair falls out in uneven patches and body hair may also be lost. The hair may re-grow on its own or treatment may be needed to encourage re-growth.

Further causes

Other causes include scarring alopecia in which various processes (e.g. burns) can permanently destroy hair follicles through scarring, with no hair re-growth possible; fungal infections (e.g. ringworm); adverse reactions to hair-care products; and trichotillomania (hair pulling or plucking) usually indicating the presence of an obsessive-compulsive disorder.

When should I see my doctor?

If your hair loss is worrying you in any way, see your doctor. Also see your doctor if your hair loss is not typical of that in other male members of your family, if you are unwell in any other way or you have recently had a major illness, injury or emotional stress. Also, see your doctor if your hair loss involves hair on other parts of your body, as occurs in alopecia areata, or is accompanied by changes in the appearance of the underlying skin, which may indicate an infection.

Tests are unlikely to be needed unless your doctor suspects that your hair loss may be due to a cause other than male pattern baldness. In this case, referral for a hair and/or skin biopsy may be suggested, as well as a thorough check of your overall health to find out if you have any other medical problems that may need treatment.

What treatments are available for male pattern baldness?

Minoxidil

Minoxidil (e.g. Rogaine) is a solution that is applied to the scalp (when dry) twice daily. Re-growth cannot generally be expected until after at least 4 months of applying Rogaine twice a day. This may be preceded by some initial hair loss as hair follicles in the resting phase are stimulated to move to the growth phase. It is not known exactly how minoxidil exerts these effects. The amount of re-growth will vary among people. Once treatment is stopped, however, the scalp will return to its previous state of hair loss within 3 to 4 months. Side effects can include a dry, red and itchy scalp. Remember that minoxidil is also used in tablet form as a prescription drug to treat high blood pressure, so using an excessive dose will not only fail to help your hair loss but can possibly affect your blood pressure and heart function. Follow the directions on the product and wash your hands after use.

Be aware that minoxidil does not cause improvement in all men who try this treatment and re-growth is variable. Minoxidil solution for hair loss is available over-the-counter from pharmacies and does not require a prescription.

Finasteride

Finasteride (brand name Propecia) is a tablet that is used to prevent further hair loss and increase hair growth in male pattern baldness in men aged 18 years and over. Finasteride works by blocking the enzyme that changes testosterone to dihydrotestosterone, the form of this male hormone that is thought to be responsible for male pattern baldness. The usual dose of Propecia is one tablet daily with re-growth or reduction of further hair loss visible after about 3 months. However, it may take 2 or more years before a noticeable effect is seen. Side effects of finasteride are uncommon and usually mild. Less than 2 per cent of treated men report a decreased libido (sex drive) and problems with their erections, which may be related to the medication.

Be aware that finasteride does not cause improvement in all men who try it. In order to decide how effective the treatment is for you, it may be a good idea to photograph your scalp before treatment and again after 6-12 months. Finasteride is only available on prescription from your doctor.

Other options

Alternative options include wearing a wig or toupee, colouring the scalp with a camouflage dye, hair transplant surgery, artificial hair fibre implantation, and scalp reduction surgery. Talk to your doctor about these options before deciding which, if any, may be suitable for you.

Unproven treatments

There are many treatments suggested for hair loss which have not been shown to be effective. These include jojoba oil, lanolin, wheatgerm oil, scalp massage and laser treatment. Again, speak to your doctor before opting for these or any other hair loss treatment options to avoid unwanted effects and spending time or money on a treatment that is unlikely to help.

Opting for no treatment

If your hair loss is due to male pattern baldness and it is not worrying you, then no treatment is needed. Wear your bald pate with pride!

Last Reviewed: 23 November 2009
myDr

References

1. Therapeutic Guidelines (eTG) [website]. Androgenetic alopecia. Dermatology guidelines, revised 2009, Feb. http://www.tg.org.au (accessed 2009, Nov 26)
myDr

myDr

myDr provides comprehensive Australian health and medical information, images and tools covering symptoms, diseases, tests, medicines and treatments, and nutrition and fitness.