Tackling Seborrhoeic Dermatitis of the Scalp: dermatological advice

Seborrhoeic dermatitis (SD) is a chronic inflammatory condition that affects areas of the skin rich in sebaceous glands, such as the scalp, face and central part of the trunk. When it affects the head, it can cause persistent dandruff, scabs, intense itching, redness and flaking that may be more or less visible.

Often mistaken for ordinary dandruff, seborrhoeic dermatitis actually has a more complex cause, linked to genetic factors and stress. It is not contagious, but it can be very troublesome and affect one’s quality of life.

What is SD of the scalp and what are its symptoms?

Seborrhoeic dermatitis of the scalp is a localised form of seborrhoeic dermatitis that affects the area covered by hair to a greater or lesser extent. It presents with persistent flaking (dandruff), itching and redness, sometimes accompanied by yellowish patches adhering to the skin. The appearance of visible dandruff on the hair or clothing is often one of the first recognisable signs.

In the most severe cases, the itching can be very intense and cause the person to scratch frequently, with the risk of:

• Wounds and abrasions of the scalp;

• Temporary hair thinning caused by trauma from scratching;

• Local skin infections, which can cause pain and swelling of the lymph nodes in the neck, may in some cases require treatment with antibiotics.

In some people, the dermatitis affects the entire scalp and stops abruptly at the hairline. In other cases, it extends beyond this, also affecting the forehead and the area behind the ears, making it even more noticeable and troublesome from both an aesthetic and social perspective.

What triggers seborrhoeic dermatitis on the scalp: the causes

There are a number of theories circulating about the causes of SD, but they have little scientific basis but can have a significant psychological impact on those affected by the condition. These include the fungal theory and the intestinal theory:

• The fungal theory suggests that seborrhoeic dermatitis is caused by the proliferation of the yeast Malassezia furfur, but it is more likely that the yeast proliferates as a result of the condition rather than being its cause.
• The gut theory, which posits that gut dysbiosis and sensitivity to certain foods necessitate special diets, is even less supported by scientific evidence.

In fact, seborrhoeic dermatitis of the scalp is a genetically determined and stress-induced abnormality in the growth of the epidermis.

Psoriasis, dandruff or seborrhoeic dermatitis: how to tell them apart

Dandruff, seborrhoeic dermatitis and scalp psoriasis are different conditions but are often confused with one another, mainly because they present with similar symptoms: flaking, itching and redness. However, correctly distinguishing between these three conditions is essential for choosing the right course of trattamento.

Remedies for seborrhoeic dermatitis of the scalp: how to choose the right ones

The first thing that springs to mind is to get hold of an anti-dandruff or anti-seborrhoeic shampoo. And that’s where the trouble starts. The supermarket and pharmacy/drugstore market is awash with anti-dandruff and anti-seborrhoeic shampoos. Which one should you choose, and how?

Shampoo for seborrhoeic dermatitis: friend or foe?

Shampoo is a cosmetic product designed to wash and cleanse the hair of grease and dirt quickly, without weighing it down or damaging it. A shampoo is formulated with surfactants (cleansing agents) and water, along with other additional ingredients.

Surfactants are the cleansing agents, but they can also irritate the skin. In fact, due to their chemical composition, virtually all surfactants are poorly tolerated by the skin. For example, sodium lauryl sulphate (SLS), which is by far the most widely used surfactant in shampoos, is considered a primary skin irritant and is used in experimental dermatology as an irritant inducer to study the effects of anti-inflammatory agents.

Other surfactants should also be regarded as irritants, so the first rule for those suffering from seborrhoeic dermatitis is not to rub the shampoo into the scalp with your fingers, in order to avoid irritation and a worsening of the condition.

In practice, however, the exact opposite happens: people with seborrhoeic dermatitis on the scalp tend to rub the shampoo in for a long time, thinking that prolonged massage will help remove the hated flakes and scabs, but this actually has the opposite effect.

Medicated shampoo for seborrhoeic dermatitis: helpful or harmful?

For many years now, shampoos have been available on the market that contain medicinal substances or active ingredients designed to target the (alleged) causes of SD. These products are known as Medicated Shampoo.

Medicated shampoo is therefore seen as a treatment for seborrhoeic dermatitis and, as such, is massaged or rubbed into the scalp or even left to work for several minutes. The conclusion is that the shampoo’s inflammatory effect – that is, its surfactant action – outweighs the ‘curative’ effect of the active ingredients it contains.

This explains the major disappointments and the constant trialling of new shampoos that is typical of people with SD

Cortisone: damage and dependency

Disappointed by medicated shampoos – which are expensive and ineffective – many people resort to the quick fix of using cortisone in its various commercial forms.

In most cases, the response to SD is almost immediate. The itching and flaking disappear. Unfortunately, once the cortisone is stopped, the condition often appears more severe than it was before treatment.

If, on the other hand, one continues to use cortisone, one risks developing cortisone tachyphylaxis – that is, the need to use increasingly frequent applications to keep seborrhoeic dermatitis at bay. By this stage, however, the cortisone has already caused damage to the scalp, such as thinning of the skin and hair loss; furthermore, any attempt to stop using it is followed by a rebound effect, with cortisone withdrawal symptoms.

For further reading: Cortisone in Dermatology: controversies and side effects

How to treat Seborrhoeic Dermatitis of the Scalp: advice from Dermaclub

The use of sulphur-salicylic cream

Sulphur-salicylic cream (Dermaclub recommends 2S Cream ) is composed of salicylic acid and colloidal sulphur, two ingredients with marked anti-dandruff properties. When you have dandruff and long hair, it is not easy to apply the cream through the hair and work it in by massaging the scalp. However, with a little patience, working in small, adjacent sections, you can apply it evenly. The sulphur-salicylic cream is applied in the evening and, if applied correctly, the hair does not feel weighed down, so there is no need to wash it the following day. In fact, during treatment with the sulphur-salicylic cream, i is advisable to wash your hair as infrequently as possible.

The frequency of application depends on the severity of the dry skin: for mild cases, once a week is sufficient, whereas for more severe cases, applications may be more frequent, up to every evening.

The use of shampoos for SD

Dermaclub recommends a shampoo formulated with a gentle, non-foaming cleansing system that rinses out quickly and thoroughly, and enriched with sulphonated ichthyol (as in Dermictiol Shampoo). Sulphonated Ichthyol is a natural compound with anti-inflammatory and anti-seborrhoeic properties. The formulation of this shampoo allows the hair to be washed even during a seborrhoeic dermatitis flare-up, minimising the pro-inflammatory effect typically associated with shampoos.

When washing your hair with Dermictiol Shampoo, you should never massage or rub it into the scalp; instead, massage it into the hair only and then rinse it out immediately.

How to prevent Seborrheic Dermatitis

SD is a recurrent form of dermatitis that often takes a chronic course. Once the condition has completely cleared up following the recommended treatment, and your scalp no longer itches or flakes, you can resume washing your hair as frequently as before, but without massaging the shampoo into your scalp to avoid causing irritation and triggering a recurrence of seborrhoeic dermatitis. If seborrhoeic dermatitis symptoms reappear but are still mild, they can be managed and brought under control simply by applying a few drops of a glycolic and salicylic acid-based lotion (such as Glicosal) to the scalp in the evening.

How I beat seborrhoeic dermatitis of the scalp: find out on the Dermaclub Forum

If you’d like to find out how other people are coping with DS, we invite you to read the many testimonials and discussions on the DermaClub Forum: you’ll find first-hand accounts, practical advice and updates on the most effective treatments.

Go to the forum and check out the relevant discussions: DermaClub Forum – Seborrhoeic Dermatitis of the Scalp

Do you have any specific concerns or would you like some advice? Post your question on the forum: our dermatologists will provide you with a detailed and expert response.