Dr Phil Kieran: What can my teen daughter do about scaly crust on her scalp? 

Seborrhoeic dermatitis most commonly starts during adolescence, when the glands produce more and different oils.

Seborrhoeic dermatitis in its mild forms is what we call dandruff, with the skin on the scalp becoming irritated and forming large flakes that fall off.

Q: My teenage daughter has developed a thick, scaly crust on her scalp. It happened shortly after a stressful period in school. She’s tried anti-dandruff shampoo, but it made no difference. Could it be a form of dermatitis?

A: Scalp irritation is a common problem people present with to a GP surgery. This case sounds like seborrhoeic dermatitis. When anti-dandruff treatments don’t work, I suggest seeing a GP to confirm the diagnosis, as it can sometimes be confused with eczema or psoriasis, which would require different treatments.

Seborrhoeic dermatitis in its mild forms is what we call dandruff, with the skin on the scalp becoming irritated and forming large flakes that fall off. The many different anti-dandruff shampoos will give you a good idea that this issue is common. Over-the-counter anti-dandruff treatments will control the condition in most people, but some are not so fortunate.

Seborrhoeic dermatitis (seborrhoea means relating to oil glands, and dermatitis is inflammation of the skin) is where the skin’s surface becomes inflamed and can overgrow. This can produce thick, waxy scales, which can be sore to remove.

The condition can extend into the eyebrows or the skin beside the nose.

It most commonly starts during adolescence, when the glands produce more and different oils.

It’s not fully understood why some people get this condition and others don’t, but it is linked with the yeast malesezzia. It has nothing to do with yeast in your diet, as it is a yeast usually present on the skin.

For approximately 60-70% of people, this doesn’t cause any problems, but, for others, the yeast invades the top layer of skin and causes inflammation and increases skin turnover.

I usually start (as you did) with OTC anti-dandruff shampoos. If these are unsuccessful, I prescribe an anti-fungal shampoo. This can be effective, but you must comply with the instructions on how long to leave it on the scalp, which is usually for five to 10 minutes. If you leave it on for longer, it’s less effective and resistance to it builds up faster. Unfortunately, seborrhoeic dermatitis is a long-term condition. It will wax and wane, triggered by the changing of the seasons or emotional stress.

Eventually, the first treatment will stop working, and your GP will suggest a second one. The goal is that the first one will work again. For some people, hydration and eating fruit can reduce the severity and frequency of flare-ups.

The condition tends to become less severe with age, only flaring up when the person is highly stressed. It should be easy to keep in remission, but getting in-person medical advice is the best next step.

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