Seborrheic dermatitis is an eczema that leads to oily patches covered with thick, yellow, greasy scales, commonly on the scalp and face.
It is also sometimes referred to as dermatitis seborrhea, in which ‘dermatitis’ refers to skin inflammation, while ‘seborrhea’ refers to excessive oiliness.
Although the exact cause is not clear, Malassezia fungus, oily skin, and underlying skin barrier impairment are thought to play a role.
Seborrheic eczema is often treated with antifungal ingredients (either in dandruff shampoos or topical creams), steroids, or immunosuppressants.
Table of Contents
What is seborrheic dermatitis?
Seborrheic eczema or dermatitis is a chronic inflammatory skin condition that can present with thick yellow scales, redness, and itching.
It can affect various parts of the body – mainly rich in sebaceous/oil glands like the scalp, face, chest, and back. Worldwide, its prevalence is around 1-5%. Males are affected more than females.
Who gets it?
Seborrheic dermatitis can be seen in three age groups:
- Infancy (first 12 months of life)
- Adolescent (after the onset of puberty)
- Adulthood (40-60 years of age)
In addition, it can be seen in immune-compromised patients (like HIV), some neurological diseases (like Parkinson’s disease, and Alzheimer’s dementia), and due to some medications.
Symptoms
Seborrheic dermatitis seen in infants usually presents with a thick yellow scale on the scalp – referred to as cradle cap. Other areas can also be affected on the body like skin folds and diaper area. It is usually self-limiting and goes away by 4-6 months of age.
In adolescents and adult populations, seborrheic dermatitis is a chronic condition. It usually presents in oil-rich areas like the face (commonly involves the nose and area in between eyebrows), scalp, and upper chest.
It is characterized by the following features:
- Scalp seborrheic eczema can lead to a buildup of thick, yellow, greasy scales or crusty spots.
- Oily, red patches covered with thick yellow scales or crusty dry skin can be seen on the face, especially on the nose, nose crease, nasolabial folds, and between the eyebrows.
- Red patches can also be seen in the beard area.
- Sometimes, the affected areas may be slightly raised forming plaques.
- In people with darker skin tones, seborrheic dermatitis may present with dark red, brown, or hypopigmented white patches.
- Ring-shaped or annular discolored spots may be seen in a type of seborrheic dermatitis called petaloid, particularly in individuals with darker skin tones
- Eyelid skin can also be affected leading to swelling, redness, and flaky/scaly skin (seborrheic blepharitis).
- Eczema patches can be found inside and around the ears.
- Red patches can be seen in the oily areas of the trunk.
- In some cases, it may involve armpits, areas under the breast, groin, or other body folds.
- Seborrheic dermatitis is often associated with itching or pruritus.
- Scratching the areas can lead to sores on the scalp and other involved areas.
The condition can vary from mild to severe. In immunocompromised, this condition is often more severe and difficult to treat. Sometimes when the disease is mild and limited to the scalp, it can present just like dandruff.
Seborrheic dermatitis vs dandruff
Dandruff is limited to the scalp and has minimal to no inflammation. Seborrheic dermatitis on the other hand can extend to other areas of the body as well and is accompanied by inflammation.
Some consider both of these conditions to be part of a spectrum of one skin condition. Also, it is really difficult to differentiate mild seborrheic dermatitis and dandruff just by looking at the scalp.
If you read my post on dandruff, you will see that the factors related to seborrheic dermatitis and its management part overlap with dandruff.
Differential diagnosis
A red rash with scaliness can be a presenting feature of many other conditions like psoriasis, atopic dermatitis/ eczema, rosacea, and systemic lupus erythematosus (SLE). This is the reason why it is important to not self-treat any skin condition.
Causes
The main reason, or pathophysiology, behind why seborrheic dermatitis occurs is still not completely clear. There are several factors that may play a role or predispose an individual to this condition.
1. Malassezia fungus
Several articles in various journals suggest the role of Malassezia in seborrheic dermatitis. Malassezia is a fungal species that is part of the normal flora of the skin. So basically, we all have it on our skin.
But why do some people get seborrheic dermatitis, and some don’t? It is still a mystery.
People with seborrheic dermatitis usually have a higher burden of Malassezia. In one study, it was seen that Malassezia was around 46% of the skin flora in people with no skin condition, 74% in people with dandruff, and 83% in people with seborrheic dermatitis.
This theory is also supported by the fact that treatment with antifungals results in a decrease in the burden of Malassezia and visible improvement (like in this study ketoconazole cream 2% reduced the number of yeast on the scalp of subjects with seborrheic dermatitis).
In addition, there is a correlation between the amount of Malassezia and the severity of seborrheic dermatitis as suggested by this study.
Malassezia can metabolize the oil on our skin with an enzyme called lipase. It results in the release of unsaturated fatty acids like oleic acid. This can irritate our skin, and cause inflammation and hyperproliferation of skin cells leading to visible redness and flaky skin.
However, the mere presence of Malassezia on the skin is not what causes it. Probably how the person’s skin reacts to it may be a contributing factor as well.
2. Oiliness of skin or scalp
The activity of sebaceous glands is largely under the control of hormones. The fact that this occurs in babies in the first few months of life, after puberty, and in adults, and thereafter the incidence decreases, favors its correlation with increased activity of oily glands in response to hormones.
However, not everyone with oily skin develops seborrheic dermatitis and some who have seborrheic dermatitis have normal or dry skin. In addition, the composition of sebum is another factor that may be a contributing factor to its occurrence.
3. Skin barrier defect
Skin barrier dysfunction is often overlooked when it comes to seborrheic dermatitis. However, this article hypothesis that barrier defect may be one of the root causes of seborrheic dermatitis (along with skin oil/sebum amount and composition).
Skin barrier defects may be the reason why Malassezia is able to overgrow on the skin. This in turn can lead to further disruption of the skin barrier by the metabolites of yeast like oleic acid, creating a cycle of chronic inflammation.
Often, we think that we need to get rid of all the skin surface oils. We end up using a lot of harsh skincare products which further damage the skin barrier.
4. Other individual-related factors
The incidence and severity of seborrheic dermatitis are associated with immune suppression, particularly in HIV/AIDS patients.
Some genetic factors (mostly seen in animal studies), emotional stress, and neurogenic factors (which can affect the oil glands) are some factors that can play a role in this skin problem.
Looking at the factors above, it is still unclear which is the root cause of this skin condition. However, we can focus on decreasing Malassezia and barrier repair to manage this condition.
Lifestyle changes
Stress is an important factor to consider when managing seborrheic dermatitis. So, in stressful times try to do things like just going on a walk, meditating, or talking to a close loved one.
A well-balanced diet is important for our overall health. Removing a big class of food can be very challenging. Rather see if any specific food item is related to any of your flare episodes. If you think you need help planning your diet, it’s best to see a professional.
Just like dandruff, increased sebum secretion is one of the possible factors related to seborrheic dermatitis. So, limiting high glycemic food may help your skin but remember that will also help your overall health as well.
Also, these are related factors and not a direct cause of seborrheic dermatitis.
In addition, be gentle with your skin. The aim of managing seborrheic dermatitis is not only to treat the current episode but also to prevent any flare in the future so gentle skin care can help with the repair of barrier dysfunction.
Treatment
Seborrheic dermatitis in infants usually goes away by itself. Massaging the area with oil and using a soft brush during the wash can loosen the scales. Over-the-counter dandruff shampoos should not be used in infants unless instructed by a treating physician.
In adolescents and adults, treatment of seborrheic dermatitis includes clearing the current flare and keeping it from coming back. Seborrheic dermatitis cannot be cured however when managed properly, one can have long periods without this skin problem.
The treatment options include antifungals, keratolytic, anti-inflammatory, and immuno-modulatory agents.
- Antifungals: These can decrease the excess Malassezia fungi. This includes ketoconazole, ciclopirox, zinc pyrithione, sulfur, and selenium sulfide. Depending on the area involved and severity, either wash-off shampoos or leave-on treatment is used. Oral antifungals may be used in severe cases.
- Keratolytic are the agents that decrease the build of dead skin. It includes salicylic acid, coal tar, and sulfur.
- Anti-inflammatory and immuno-modulatory agents: These decrease inflammation or affect how our immune system reacts. These should only be used under the guidance of a treating physician. This group includes steroids in various strengths which can be in the form of lotion, creams, ointments, or shampoos, and calcineurin inhibitors like tacrolimus ointment (brand name Protopic), pimecrolimus cream (brand name Elidel).
How to use treatment products will depend on the specific area.
- Scalp: When using shampoo or a wash, your doctor may recommend you leave the foam on the scalp for a few minutes to allow the ingredients to work.
- Face: Your doctor may recommend a wash or a topical cream to treat the affected areas. It is also important to be gentle when using these treatment products.
- Eyelids: A gentle wash may be recommended to clean the skin of the eyelids, followed by the application of a topical treatment.
Now let’s dive deep into some of the over-the-counter ingredients and products that can be helpful for seborrheic dermatitis.
Antifungal and keratolytic
1. Ketoconazole
This is an antifungal which can decrease the burden of Malassezia on the skin. It alters the fungal membrane and prevents its growth. It may be helpful in seborrheic dermatitis because of its anti-inflammatory properties as well.
For scalp seborrheic dermatitis, it is often used in the form of shampoo. For other areas, cream, gel, or foam may be used. You can get 1% ketoconazole shampoo (Nizoral) over the counter. However, to get 2% shampoo or other forms, a prescription is required in the USA (in some countries 2% is available over the counter).
2. Zinc pyrithione
Zinc pyrithione is found in many over-the-counter dandruff shampoos, face washes, and bar soaps. Zinc pyrithione has antifungal and antibacterial properties. It can decrease the burden of Malassezia which can help the skin to recover from the skin barrier dysfunction.
It is usually present in a particulate form in formulations and gets deposited on skin and hair follicles getting released over time.
In the US – in wash-off products, it can be used at a concentration of 0.3 to 2 percent, and in leave-on products, it can be used at a concentration of 0.1 to 0.25 percent.
Read more: Best shampoos with zinc pyrithione and Zinc pyrithione for face
3. Sulfur
Sulfur can be beneficial for seborrheic dermatitis because of its keratolytic and antifungal properties. It reacts with the cysteine amino acid in the keratinocytes resulting in the shedding of cells.
Our skin cells and flora can convert sulfur to pantothenic acid which is toxic to the fungi.
Products with sulfur can stain metals, light-colored hair, or clothing. Also, the smell is often unpleasant.
4. Selenium sulfide
Selenium sulfide is an effective anti-fungal that can decrease Malassezia on the skin surface. It can also decrease cell turnover which can reduce the flakes in the hair and itching. It is available at a concentration of 1% over the counter (a higher concentration of 2.5% is available with a prescription in the US).
It can also disrupt the fungal biofilm and hence may be beneficial in more chronic persistent cases. It can discolor light-colored hair and stain some metals.
Selenium sulfide is found in popular shampoos such as Head & Shoulders Clinical Strength Dandruff Shampoo and Selsun Blue Dandruff Shampoo.
5. Climbazole
Climbazole is also an azole antifungal like ketoconazole which can decrease the amount of Malassezia. One study evaluated 0.65% climbazole shampoo on seborrheic dermatitis of the scalp and found it to be effective.
Another small study evaluated a cream containing climbazole and piroctone olamine (Bioderma Sensibio DS+ cream) and found it to be effective in improving seborrheic dermatitis. This cream also has some other anti-inflammatory ingredients which might be contributing to its effects.
6. Ciclopirox olamine
Ciclopirox olamine has antifungal, antibacterial, and anti-inflammatory properties. Ciclopirox shampoo 1% is available through prescription in the United States for the treatment of seborrheic dermatitis. In some countries, it is available over the counter.
One study comparing 1.5% ciclopirox olamine and 2% ketoconazole, found both of these comparable in efficacy in treating scalp seborrheic dermatitis. Ciclopirox olamine 1% shampoo has been evaluated in multiple studies (1,2,3) and found to be effective for scalp seborrheic dermatitis.
7. Piroctone Olamine
This is an antifungal agent that can benefit by decreasing Malassezia. It is found in some topicals and dandruff shampoos. Promiseb cream is a nonsteroidal cream with some anti-inflammatory ingredients and piroctone olamine. It is available in the US by prescription.
Several studies have evaluated the efficacy of this cream. One study compared it with a low-potency steroid cream and found both to be equally effective in reducing mild to moderate seborrheic dermatitis of the face.
Atopiclair cream has some similarities to the composition of Promiseb cream and is available over the counter in some countries.
Another study supported financially by Isdin evaluated the brands’ facial cream containing piroctone olamine, stearyl glycyrrhetinate, and zinc PCA and found it to be effective in improving seborrheic dermatitis on the face.
8. Coal tar
Coal tar decreases the production of skin cells, reducing redness, inflammation, and irritation. It is an effective ingredient for seborrheic dermatitis.
It can make the treated skin more sensitive to the sun so make sure to protect your skin. It’s best to start with a lower concentration to avoid skin/scalp irritation. Products with coal tar often have an unpleasant smell.
9. Salicylic acid
Salicylic acid is an exfoliant and can reduce the build-up of dead skin cells. Its anti-inflammatory properties can be beneficial for seborrheic dermatitis as well. In addition, it can aid in the penetration of other active ingredients.
Related Post: Best Face Cleansers for Seborrheic Dermatitis
Moisturizers and other skincare ingredients
A lot of people think that a moisturizer will make seborrheic dermatitis worse. However, in recent years the importance of skin barrier has emerged in various skin conditions including seborrheic dermatitis.
The aim is to use an antifungal ingredient that will decrease Malassezia and use barrier repair products like moisturizers to heal the skin.
Read details: Best moisturizers for seborrheic dermatitis and Best serums and toners for seborrheic dermatitis
1. Moisturizers
Barrier repair doesn’t necessarily require a moisturizer with ceramides. Yes, there are a lot of moisturizers with ceramides and if you like one and include that in your routine, it can immensely help your skin. However, even a simple moisturizer can aid in barrier repair.
Many products intended to benefit seborrheic dermatitis can be harsh. So, using a moisturizer can help you tolerate these products better.
There are so many well-formulated moisturizers on the market and some of these have additional skin-loving ingredients or one or more antifungal ingredients to decrease Malassezia.
2. Niacinamide
Niacinamide is a versatile ingredient that is found in several serums, moisturizers, and sunscreens. It can enhance the skin barrier and decrease inflammation which can help with barrier dysfunction in seborrheic dermatitis.
One study evaluated a 4% topical nicotinamide cream and found it to be useful for facial seborrheic dermatitis.
Many serums these days have a higher concentration of niacinamide which may or may not irritate your skin. So, I would start with a lower concentration to make sure there is no irritation.
3. Urea
Urea is another ingredient that can decrease the buildup of dead skin cells and enhance the skin barrier. There is a study where a solution of urea, lactic acid, and propylene glycol when used topically resulted in an improvement of seborrheic dermatitis symptoms.
Note: Urea can irritate rosacea-prone skin, so be cautious if you have a coexistence of rosacea and seborrheic dermatitis.
4. Azelaic acid
Azelaic acid has anti-keratinizing, anti-inflammatory, and antioxidant properties. It also has antimicrobial properties. It can suppress the growth of Malassezia as suggested by a study done in a lab. It may decrease sebum production as well.
These properties make it useful for the treatment of seborrheic dermatitis. One article discusses two cases of seborrheic dermatitis responding well to treatment with azelaic acid 15% gel vehicle.
Seborrheic dermatitis can coexist with rosacea (as high as 35%). Treatment of one can make the other worse. So, if something treats both like azelaic acid – that will be a great option.
I have personally had great results from using azelaic acid in my routine. However, azelaic acid can be drying and irritating so start slow with a lower concentration or use it over moisturized skin.
Read more: Best azelaic acid products
5. Licorice extract
It is known for its anti-inflammatory properties and can help seborrheic dermatitis by decreasing inflammation. It has also been found to be useful for atopic dermatitis.
6. MCT oil
MCT aka medium-chain triglycerides are commonly found in coconut oil and palm kernel oil. Some people with seborrheic dermatitis had good results from using this. It may be due to its antifungal properties and also due to its moisturizing properties.
BIOM8 – Skin Conditioning Oil is a product based on MCTs – caprylic/Capric Triglyceride and tricaprylin (Caprylic Triglyceride).
7. Honey
Honey has several benefits for the skin due to its antimicrobial, anti-inflammatory, and humectant properties. Some have benefited from using honey as a face mask.
Personally, I have tried them but did not have a lot of effects other than moisturizing effects. You can use any type of honey. However, some people prefer to use manuka honey (produced by bees who pollinate the flower Leptospermum scoparium).
Note: If you are allergic to bee-related products, probably skip using honey.
8. Essential oils
Some essential oils have antifungal properties (like tea tree oil) and can be beneficial for seborrheic dermatitis. However, they should not be used directly on the skin. They should be diluted to avoid the risk of contact dermatitis and other negative reactions.
9. Other Ingredients to look for in your skincare products
In addition, several other ingredients like oats, green tea, Centella, and panthenol can benefit by decreasing inflammation and repairing the skin barrier.
Read more: Skincare Routine for Facial Seborrheic Dermatitis and Products to Avoid with Seborrheic Dermatitis
Summary
Seborrheic dermatitis in adults is a chronic condition and cannot be completely cured. However, when properly managed, the number of active flares can be significantly reduced.
It can affect various parts of the body. A product that may be fine for use on the scalp or body, may not be gentle enough for facial skin.
Similarly, very thick ointments may not be cosmetically appealing, so you might have to choose a skincare product depending on the area you are treating. Active flare and severe symptoms need to be managed by a healthcare professional.
Disclaimer: This blog post is for information purposes only and does not replace medical advice.