Hair loss: Hair loss during a severe illness of any kind (and during pregnancy) many hairs grow in the same phase at the same time. When normal health returns they all go into the eight-week resting phase then they all start growing at once, and lots of hair falls out. This, however, indicates that growth is occurring and the appearance will soon return to normal.

Someone who is totally hairless may otherwise be in perfect health, but that is little consolation to you if your hair is falling out. Alopecia areata is the name given to a common but ill-understood condition in which patches of scalp hair fall out and there is no immediate growth of the bald patches. These patches usually have a clear edge and are often round or oval in shape. The cause of this type of hair loss is unknown, although most people who suffer from it are often under some kind of stress. In such cases, dealing with the source of the stress usually restores normal hair growth. There is no other really effective treatment, although steroid injections into the scalp sometimes seem to make a difference. The outlook is unpredictable: sometimes the conditions progresses to complete loss of hair from the scalp, eyebrows, and body (alopecia totalis) but more often the patches come and go for a few months, and then there is a gradual return to a full growth of hair.

If your hair seems to be falling out in patches, consult your doctor. There are several other possibilities, the most likely is a fungus infection of the scalp (ringworm – which has nothing to do with worms) and will clear up quickly with treatment with an antifungal paste.

Male pattern baldness: Whether or when a man goes bald is determined by his genes, not his health. The inheritance of baldness is complicated, if a boy wants to know whether he’s likely to become bald at an early age, he should look not at his father but at his mother’s male relatives : his uncles and his maternal grandfather. He is likely to have inherited the same sort of hair.

Some young men begin to lose hair in their late teens, thinning at the sides of the forehead and in the middle of the scalp at the back. Nothing can be done to slow down this process. Vast sums of money are spent by young men on various treatments for premature baldness. These include several types of hair transplantation and the application to the scalp of a drug called minoxodil. These treatments are expensive and at best they only postpone baldness by a few years. If there was a really good treatment, it would have been given to film and pop stars; in fact, the ones who have gone bald early have stayed bald, except the ones who wear wigs or who have had hair transplants. It may be some consolation to know that men only go bald if they have normal sex hormones, after removal of the testes, the hair on the head grows thick while the hair on the face disappears.

Excess hair: The amount of hair on the body varies enormously among the different human races. Asiatic races have little hair, whereas among Mediterranean, Indian, and Arabic peoples dense hair on the chest and back is common in men, and women usually have substantial amounts of hair on the arms, legs, and even the face. You can expect to grow up looking like your relations of the same sex, and there is little you can do about it. Nevertheless, many young men become distressed because they have little or no growth of facial hair, whereas young women are more often concerned about unwanted dark hair. If you’re worried about the amount of hair on your face or body - either too much or too little – look at the rest of the family. It is reasonable to consult your doctor only if you are clearly different. Vigorous growth of hair may also be a side effect of some prescription drugs.
Medical conditions causing excess hairiness in women are rare, but they do occur. A young woman whose body hair suddenly becomes more dense or who develops other symptoms suggesting a hormonal imbalance, such as change in the voice or menstrual disturbance, should certainly see a doctor. If there is an underlying hormonal disturbance, it should be treated, and effective treatments are available.

Someone who has simply inherited a tendency to have a lot of body hair and does not like it has several options. Excess hair can be removed by depilatory creams bought from the pharmacy or by shaving, and there is no evidence to support the folklore that these treatments encourage the hair to grow quicker; they don’t. Bleaching the hair makes it less obviously visible. Hair can also be permanently (but painfully) removed by electrolysis. Waxing, which is best done professionally, also seems to reduce hair growth. In many case, it may be worthwhile to postpone a decision about the method of hair removal unit the adolescent hormonal upsets are over.

Dandruff and seborrheic dermatitis: People who have dandruff are usually easy to spot: the shoulders of their clothes are dusted with a mass of white specks that have come off their scalp, and they may also scratch their heads a lot. Dandruff is the name for the specks (which are in fact scales of dead skin) from the scalp. The underlying disorder that causes dandruff is called seborrheic dermatitis, and it leads to the skin of the scalp becoming midly inflamed and thickened. Itching of the affected scalp leads to scratching, and the scratching scrapes off masses of yellowish white, greasy scales that shower down onto the person’s shoulders.

Often the only part of the skin affected by seborrheic dermatitis is the scalp, but it may also cause patches of inflamed, scaly, crusted skin in other hair regions such as the eyebrows, the groin, and the armpits. The creases between the nose and the corners of the mouth may be affected, as may the whole of the beard area of the face in men.
Simple dandruff will usually clear up if the hair is washed twice a week with an antidandruff shampoo, obtainable from a pharmacy or supermarket. These shampoos, which contain chemicals such as selenium and sinc pyrithione, are usually effective, but someone with a tendency to dandruff may continue to have symptoms for their whole – lives and may need always to use a dandruff shampoo.

More extensive seborrheic dermatitis needs treatment by your doctor. Unfortunately there is no certain cure. The inflammation usually improves quickly after treatment with a steroid cream, but it often returns when treatment is stopped. Creams based on suffer or containing antifungal drugs are sometimes effective. The condition usually improves and often disappears in early adult life.