Cracked heels: prevention and treatment for healthy, beautiful feet
06/09/2023Sensitive skin: tips for daily comfort
06/09/2023Seborrheic dermatitis on the scalp: trickier to treat
Seborrheic dermatitis is one of the most common and well-known forms of dermatitis.
It has two variants:
- Seborrheic dermatitis on the scalp
- Seborrheic dermatitis on the body
Seborrheic dermatitis on the scalp
Seborrheic dermatitis causes dandruff, so it is commonly mistaken that seborrheic dermatitis and dandruff are the same thing.
Dandruff, that is, the flaking of small white lamellae, can also be caused by external factors.
The mains one are:
- Use of harsh shampoos
- Inadequate rinsing
- Frequent washing
- Scratching the scalp during washing
- Hair cosmetics (lotions, rubs)
- Hair salon treatments (dyeing, styling, etc.)
- Excessive drying with hot air
In such cases, when the cause is removed, the dandruff will simply disappear.
In contrast, and unlike simple dandruff, seborrheic dermatitis is a disorder of the maturation and desquamation of the stratum corneum and should be considered a minor, yet very real, pathological skin condition.
The causes of seborrheic dermatitis are traced back to the individual, in that they are mainly due to genetic predisposition and/or environmental factors, such as stress and seasonality.
Seborrheic dermatitis will worsen when subjected to the external factors mentioned above but, unlike simple dandruff, it will not heal by eliminating them. Seborrheic dermatitis of the scalp is barely visible in those with hair.
Seborrheic dermatitis can often be spotted with the presence of dandruff on the hair or clothing. The condition often causes itching and the will to scratch.
In bald individuals and in more severe forms of seborrheic dermatitis, adherent plaques composed of yellowish scales can be seen.
In addition to desquamation of silver-colored lamellae, seborrheic dermatitis is characterized by scalp redness and itching.
Debunked theories on the causes of seborrheic dermatitis on the scalp
Seborrheic dermatitis is caused by an altered reactivity of the epidermis, often linked to a genetic predisposition and aggravated by stress. There are some theories about the causes of seborrheic dermatitis, however these are often based on little to no science, but can still alarm patients. Among such supposed theories are that of fungus and the intestinal theory. According to the former, seborrheic dermatitis is caused by the proliferation of the Malassezia furfur but yeast. This is highly doubted, as it is much more likely that the yeast proliferates as a consequence of seborrheic dermatitis, rather than because of it. Instead, the intestinal cause theory puts intestinal dysbiosis and reactivity to some foods at the root of seborrheic dermatitis. While such a theory suggests specific diets should be followed in order to overcome the condition, there is little scientific evidence to support any of this.
Generally, seborrheic dermatitis on the scalp does not cause particular discomfort, but will likely cause frustration due to the constant presence of dandruff on the hair or clothes. In some cases, however, seborrheic dermatitis can be very itchy and will cause the individual to continuously scratch the area, to the point of causing hair loss due to trauma.
This causes some areas to be affected by hair thinning and/or cuts or grazes caused by scratching. Sometimes, seborrheic dermatitis affects the whole scalp area, but stops along the hairline. In other cases, seborrheic dermatitis extends outside the hairline, which makes it particularly visible and even more bothersome. At-risk zones are the forehead and retroauricular area.
What to do in cases of seborrheic dermatitis on the scalp
As soon as the first signs of seborrheic dermatitis appear, the knee-jerk reaction is to buy an anti-dandruff or anti-seborrheic dermatitis shampoo. Shops and pharmacies are full of such products, and here within lies the problem Which one should be chosen? The answer is probably none.
Shampoo: friend or foe
Shampoo is a cosmetic product used to wash and clean the hair from greasy and dirt. It’s quick and doesn’t weigh down or damage hair. Commercially-available shampoo is formulated with surfactants (detergents), water and other ingredients. Surfactants are the cleansing component of shampoo, but are also the most irritative for the skin, due to their chemical composition that is poorly tolerated by the skin. For example, sodium lauryl sulfate (SLS) is by far the most common surfactant in shampoos, but is considered a primary irritant for the skin to the extent that it is used in experimental dermatology as an irritation inducer in order to then assess the efficacy of anti-inflammatories. Oftentimes, those with seborrheic dermatitis believe that it is important to massage shampoo vigorously into the scalp, in a bid to get rid of dermatitis scales and crusts. However, doing so causes the exact opposite to happen. Indeed, the first rule for those who suffer from seborrheic dermatitis is not to massage shampoos into the scalp, which will help to reduce irritation and will prevent the worsening of the dermatitis.
Medicated shampoo for seborrheic dermatitis
For many years, medicated shampoos have been available for cases of seborrheic dermatitis. These shampoos contain active ingredients or medicine within their list of ingredients. Medicated shampoo is often perceived as a cure for seborrheic dermatitis and, as such, is often massaged or rubbed into the scalp, and/or even left to act for minutes. As medicated shampoo contains surfactants, however, it causes inflammation that outweighs the so-called ‘curative’ properties of any of its other ingredients. This can cause the individual great disappointment and they begin a cycle of trying new shampoos in vain.
Cortisone: damage and dependency
Disappointed by the ineffectiveness and high cost of medicated shampoos, many people with seborrheic dermatitis (SD) turn to corticosteroids in various forms. Initially, the response is almost immediate, with relief from itching and flaking. However, once the corticosteroid is discontinued, the SD often returns more aggressively than before. Prolonged use of corticosteroids can lead to tachyphylaxis—a decreased response requiring higher doses—and long-term damage, such as skin thinning and hair loss. Attempts to stop usage can also trigger rebound effects and withdrawal symptoms.
See also: Cortisone in dermatology: when it is a medical disease
DermaClub’s suggestions for treating seborrheic dermatitis on the scalp
2S Cream
2S Cream is composed of salicylic acid and colloidal sulfur, which are two ingredients with strong properties that combat seborrheic dermatitis. 2S Cream should be applied in the evening. If applied correctly, the hair should not be weighed down and it will not be necessary to shampoo the hair the next day. Note that in individuals with long hair, the application of 2S can be trickier, as it must be applied evenly and in such a way that it penetrates the scalp through the hair. During treatment with 2S Cream, stagger hair washing throughout the week as far as possible. The frequency of 2S Cream application will depend on the intensity of the seborrheic dermatitis. In mild cases, one application per week is enough, but in more intense forms, nightly applications may be required.
Dermictiol Shampoo
Dermictiol Shampoo is a delicate, non-foaming shampoo with the natural, anti-inflammatory ichthyol sulfonate. Dermictiol Shampoo cleanses the hair and allows for quick, complete rinsing, while avoiding the inflammation that most other shampoos cause people with seborrheic dermatitis. Apply Dermictiol Shampoo to the hair, taking care not to rub or massage it into the scalp, before immediately rinsing well.
How to prevent seborrheic dermatitis
Seborrheic dermatitis is a relapsing, often-chronic dermatitis. After following the suggested treatments and the dermatitis, itching and scaling have all disappeared, more frequent hair washing can resume. Nonetheless, it is important to always avoid massaging the shampoo into the scalp to avoid irritation and reduce the risk of seborrheic dermatitis returning.
Should mild symptoms of seborrheic dermatitis return, a few drops of Glicosal Lotion can be rubbed into the scalp in the evening to send the initial signs of dermatitis into remission.