Table of Contents
What is Seborrheic Dermatitis?
Seborrheic dermatitis is a chronic erythematous dermatitis that occurs with red areas and flaking of the surface layer of the skin (epidermis). There are various clinical forms depending on the age and the location which is affected.
This papulosquamous disorder affects sebum-rich areas of the scalp, face, and body. In addition to sebum, seborrheic dermatitis is also associated with Malassezia (Pityrosporum – type fungi) , immunological disorders, and complement activation. The Malassezia organisms are probably not the exact cause but a cofactor associated with depression of the
The Malassezia organisms are probably not the exact cause but a cofactor associated with depression of the T-cells increased sebaceous levels and activation of the alternative complement pathway. People predisposed to this type of dermatitis may also have some sort of dysfunction of the skin barrier.
Seborrheic dermatitis affects both infants and adults and can vary from mild to very severe form covering the entire body to a state of erythroderma .
Seborrheic dermatitis is one of the most common skin manifestations of HIV infection. It occurs in 3-5% of the general HIV-uninfected population but in up to 85-95% of patients with advanced HIV infection .
Seborrheic dermatitis may be part of a serious disease such as Alzheimer’s disease (Leiner disease), which is diagnosed even in infants and usually occurs with diarrhea, growth disorders, generalized seborrhoeic dermatitis and other immunodeficient disorders.
Seborrheic dermatitis can include an inflammatory response to the proliferation of the species of Malassezia, although this theory is not proven yet. The main species found on the scalp, are Malassezia globosa, Malassezia furfur (Pityrosporum ovale) and Malassezia restricta .
Yeasts produce toxins that irritate and inflame the skin. It seems that patients with seborrheic dermatitis have reduced resistance to yeast. However, the rate of colonization of the affected skin may be lower than the area of intact skin.
It was found that only saturated fatty acids promote the growth of Malassezia. Studies have also shown that while the number of M. globosa and M. restricta does not correlate directly with the presence and severity of dandruff, the healing process is directly correlated with the improvement of flaking.
Furthermore, in the individuals that are more susceptible to dandruff oleic acid, an unsaturated fatty acid and a metabolite of Malassezia, causes peeling even in the absence of Malassezia by direct effects on the skin barrier of the patient.
These findings support the following hypothesis: Malassezia hydrolyzes human sebum, releasing a mixture of saturated and unsaturated fatty acids. Microorganisms take their necessary saturates, leaving both saturated and unsaturated fatty acids.
Unsaturated fatty acids penetrate the stratum corneum. Due to their structure, they are breaking the barrier function of the skin. This barrier violation response induces irritation, which leads to dandruff and seborrheic dermatitis development.
Studies have also shown that genetic, hormonal, immune and environmental factors are also related to the manifestation of seborrheic dermatitis.
This condition is usually aggravated by changes in humidity, changes in seasons, trauma (eg scratching), lack of sleep, emotional stress or reduced overall health. The severity varies from mild dandruff to exfoliative erythroderma. Seborrheic dermatitis can be worsened by Parkinson’s disease  and AIDS.
Multiple medications may exacerbate or induce seborrheic dermatitis. These drugs include auranofin, aurothioglucose, buspirone, chlorpromazine, cimetidine, ethionamide, fluorouracil, griseofulvin, haloperidol, interferon alpha, lithium, methoxsalen, methyldopa, phenothiazines, psoralens, stanozolol, thiothixene and trioxsalen.
According to The National Center for Biotechnology Information, the condition „affects approximately 11.6% of the general population and up to 70% of infants in the first three months of life may have the condition.” 
The usual onset of seborrheic dermatitis occurs in puberty. It peaks at age 40. Elderly people usually have milder forms of seborrheic dermatitis.
Seborrhea is manifested in various forms, such as dandruff, dense scaling on the scalp, reddening of the face or underarms, open red spots under the chest, etc.
Although the apparent feeling about some of these conditions is more about “dryness,” the wetting of the affected skin only worsens their symptoms. In other cases, at first glance, the skin appears oily, or even extremely dry.
Seborrhea is a skin disease due to both too little sebum and too much sebum on the scalp. It is a form of skin inflammation (dermatitis) of unknown origin.
The reasons for the appearance of seborrheic dermatitis still remain unclear. There are various factors that may be causing the emergence of the condition.
One of the predisposing factors is the immunosuppression (a situation in which the body’s immune system is intentionally stopped from working, or is made less effective, usually by drugs) – for example, in people with HIV infection.
In people who have normal immune status, the condition is usually due to hereditary predisposition. It is possible that some forms of seborrheic dermatitis precede the onset of psoriasis.
Severe scalp seborrhoeic dermatitis can resemble psoriasis. In psoriasis, the scales are thicker and whiter and the face is not usually affected.
Here are some of the most frequently cited factors responsible for seborrheic dermatitis:
The role of seborrhea
Seborrhea is associated to the presence of skin that looks oily. Seborrhea, however, is always associated with increased production of sebum by the sebaceous glands.
Even when seborrhea is a predisposing factor, you should always have in mind that seborrheic dermatitis is not a disease of the sebaceous glands.
The high incidence of seborrheic dermatitis in infants corresponds to the size and activity of sebaceous glands in this age. In adults, however, the activity of the sebaceous glands is peak during puberty, which does not correspond to the peak incidence of seborrheic dermatitis, which is decades later!
Another feature is related to the areas that are affected by seborrheic dermatitis – face, ears, scalp, upper body. In these areas, there are greater numbers and more densely arranged sebaceous glands.
Apart from seborrheic dermatitis, these areas are usually affected by acne.
In a study of the sebaceous glands under the microscope in a human suffering from seborrheic dermatitis, it has been found that the glands have larger than the usual size.
The study of the oily secretions reveals that its quantity is not increased, but there is a change in the proportion of the various lipids containing.
Seborrheic dermatitis is more common in people with neurological diseases such as Parkinson’s. Symptoms of such diseases are related to increased sebum secretion.
Role of microorganisms
The hypothesis about the role of various bacteria or fungus still cannot be completely proven, although in some patients with seborrheic dermatitis there are isolated microorganisms in large quantities located exactly on the affected areas.
Similarly, in newborn babies, Candida albicans is often available. However, specific studies did not confirm that their contribution for the occurrence of seborrheic dermatitis.
Aerobic bacteria can be isolated from the scalp of patients with seborrheic dermatitis. An interesting fact is that in patients with seborrheic dermatitis Staphylococcus aureus is rarely isolated. The bacteria that occurs in acne – Propionibacterium acnes can also be isolated in smaller numbers.
Malassezia is lipophilic (lipid-dependent) fungi that compose part of the normal human skin flora, but are now also recognized to play a role in skin diseases development.
In patients with seborrheic dermatitis its’ amount is even greater and for people with dandruff, its’ quantity is almost two times higher than in the healthy skin. Due to these facts, many authors support the role of this microorganism.
Due to these facts, many authors support the role of this microorganism in the development of Seborrhea. It’s further overgrowth causes even more severe inflammation.
Role of medicines
Some medicines can also lead to seborrhoea development.
The most often cited drugs include formulations with arsenic, methyldopa, sinetidin
Note that the connection between the intake of drugs and the skin condition is not very clear because seborrheic dermatitis is a widespread disease.
Role of the nervous system
Very often seborrheic dermatitis is associated with various neurological problems. Such conditions include:
Emotional stress is a common cause pushing the disease.
Role of physical factors
It is assumed that skin blood flow and skin temperature may relate to the occurrence of seborrheic dermatitis. Seasonal variations in temperature and humidity are also related to seborrheic dermatitis flare-ups. Low temperatures in autumn and winter and low humidity in rooms with central heating usually worsens the course of the disease.
One of the interesting synonyms of seborrheic dermatitis is flannel eczema (eczema flannelaire) and it is due to the fact that the friction of coarse textile clothing to the skin may worsen the condition.
The role of dietary deficiency
There is a disease which is due to zinc deficiency and proceeds with skin rash similar to that of seborrheic dermatitis. However, it is demonstrated that the inclusion of zinc does not lead to improvement of seborrheic dermatitis.
There are discussions about the connection between biotin deficiency and food allergies in infants as possible triggers for the onset of seborrheic dermatitis. This link has not been confirmed emphatically yet.
The following factors are sometimes associated with severe seborrheic eczema in adults:
Oily skin (seborrhea)
Genetic tendency or a family history of psoriasis
Immunosuppression – organ transplants, HIV, etc.
Neurological and psychiatric diseases – Parkinson’s disease, tardive dyskinesia, depression
In infants, seborrheic dermatitis appears as milk crusts or as eruption or erythroderma in the skin folds. Infantile seborrheic dermatitis affects babies under the age of 3 months and usually resolves within 6-12 months. In children, excessive intake of vitamin A can lead to seborrheic dermatitis. The lack of biotin, pyridoxine (vitamin B6) and riboflavin (vitamin B2) may also provoke the condition.
The clinical picture of seborrheic dermatitis is characterized by the intermittent occurrence of the active phases of the disease with stinging, scaling and itching, alternating with inactive periods. The activity increases in the winter and early spring, the relapses frequently occur during the summer.
The active phases of seborrheic dermatitis can be complicated by a secondary infection in the intertriginous areas (where two skin areas may touch or rub together.
Examples of intertriginous areas are the axilla of the arm, the anogenital region, skin folds of the breasts, between digits and on the eyelids. (They may also become red, swollen and flaky).
Candida overgrowth is very common in baby napkin dermatitis (nappy rash). Such babies may have diaper dermatitis – Variation of seborrheic dermatitis or psoriasis.
Generalized seborrheic erythroderma  is rarely present. It occurs more frequently in association with AIDS, congestive heart failure, Parkinson’s disease and immunosuppression in premature infants.
The appearance of seborrheic dermatitis of the scalp may vary from slightly dropping flakes to diffuse, widespread separation of large, thick crusts. The presence of plaques is rare. Seborrheic dermatitis of the scalp can spread on the forehead, back of the neck and postauricular skin, as with psoriasis disease.
Seborrheic skin lesions presented as loss of fine or greasy scales on red, irritated skin. Infectious eczematous dermatitis with secretion and crusting suggests secondary infection. Seborrheic blepharitis (Eyelid inflammation) may be present. The condition is characterized by less inflammation than staphylococcal blepharitis but with more oily or greasy scaling.
The distribution of the lesions follows the greasy and hairy areas of the head and neck, scalp, forehead, eyebrows, under the lash line, nasolabial folds, chin and postauricular skin. There may be damage to skin submental (under the chin area).
Sometimes two separate models of seborrheic dermatitis affecting the torso may appear. The most common model is annular or geographical petaloid flaking. Rarer variations can be observed on the torso and the neck with peripheral scaling imitating pityriasis rosea (pink lichen).
The diagnosis of seborrheic dermatitis can be made by a specialist dermatologist usually based on clinical findings and observation. In people with exfoliative erythroderma may be needed skin biopsy ( is a simple medical procedure in which a sample of your skin is removed and tested in a laboratory) and fungal culture in order to exclude the presence of tinea kapitis, although it is a rare condition in adults. Dermatological findings regarding seborrheic dermatitis are usually nonspecific and include hyperkeratosis, acanthosis, focal spongiosis, parakeratosis.
Differential diagnosis is made with atopic dermatitis, candidiasis (cutaneous), allergic contact dermatitis, irritant contact dermatitis, dermatological manifestations of gastrointestinal disease, dermatomyositis, drug-induced eruptions, drug-induced photosensitivity eritrazma, impetigo, intretrigo, Langerhans cell histiocytosis, lupus erythematosus, pemphigus erythematosus, pemphigus foliaceus, perioral dermatitis, pink lichen, rosacea, tinea kapitis, korporis tinea, tinea kruris.
Early treatment of exacerbations of the disease symptoms is highly recommended. Behavioral modifications are particularly useful for the reduction of excoriations located on the scalp.
Pharmacological agents that can be used include:
- For short-term use – topical corticosteroids 
- For damaged skin – ketoconazole, ciclopirox naftifine or, alternatively calcineurin inhibitors (eg pimecrolimus, tacrolimus), sulfur or sulfonamide combinations, or propylene glycol
- For acute crises – Class IV or a lower class corticosteroid creams, lotions or solutions
- In severe and refractory lesions – systemic Ketoconozale, Ciclopirox or fluconazole 
The treatment of dandruff  may include:
More frequent shampooing as well as longer soaping. Some of the best shampoos for seborrheic dermatitis you can find here.
The application of hairspray or similar hair products is not recommended
Using shampoos containing salicylic acid, tar, selenium, sulfur or zinc, selenium sulfide (2.5%), ketoconazole and ciclopirox – may help by reducing the colonies of the yeast Malassezia on the scalp.
These shampoos can also be used for lesions on the torso and the beard area but can cause inflammation in the facial area.
The best way to relieve seborrheic dermatitis symptoms is preventing or controlling the provocative factors, while always paying attention to your skin condition.
On this link, you will be able to check the most effective products you can purchase online in order to moisturize your skin and reduce the redness and irritation (the products listed are the best-selling ones available Online; positive and negative aspects are included).
Apple cider vinegar:
This method involves soaking the affected skin in a mixture of apple cider vinegar and water for a few minutes. The concentration of the vinegar should be lower in this method (5:1 – ACV-water).
You can also wash your hair with the mixture. The only thing you should remember: do not rinse it out (there is any odor once it’s dried).
Apple cider vinegar is a natural antibacterial agent and ph balances my skin to the acidic level it needs to be to fight the annoying symptoms of seborrheic dermatitis.
Honey is a potent broad-spectrum antibacterial and antifungal food.
It works a treat for removing the fungus that causes seborrheic dermatitis, both internally and topically.
A proportion of 90% raw honey and 10% pure water is mixed together and then and then applied to the skin every other day (left on for three hours before washing off with warm water ). On the alternate days you are not doing this, just apply the honey as a cleanser morning and evening – use the same mixture on your the affected areas.
This process is to be continued for 4 weeks.
The benefits of using coconut oil are numerous. This extremely valuable product fights with seborrheic dermatitis symptoms. Coconut oil applied to the skin has been shown to help reduce excess yeast,
Coconut oil applied to the skin has been shown to help reduce excess yeast, microbes, and fungus that can lead to irritation, too much oiliness or dryness. If possible, apply the coconut oil before going to bed.In the morning, wash it off from the scalp with shampoo or tar soap.
Garlic is a proven immune strengthener. It is an excellent product for the treatment of seborrheic dermatitis.Mash 6-7 peeled garlic cloves mixed with some honey. The remedy can be applied on the affected area and left on for about an hour.
The mixture facilitates healthy hair growth and thereby reduces dandruff, preventing hair loss. Garlic function is to actually increase blood circulation in the scalp.
Choosing Topical Corticosteroids
Topical antifungals for seborrhoeic dermatitis
Dandruff: How to treat
Malassezia species and seborrheic dermatitis.
LAYERS OF THE SKIN: The Epidermis
Causes and features of erythroderma.
GUIDE FOR HIV/AIDS CLINICAL CARE : Seborrheic Dermatitis
Epidemiologic Study of Malassezia Yeasts in Seborrheic Dermatitis Patients by the Analysis of 26S rDNA PCR-RFLP
A laboratory-based study on patients with Parkinson’s disease and seborrheic dermatitis: the presence and density of Malassezia yeasts, their different species and enzymes production.