Seborrheic Dermatitis – The Ultimate Guide

Seborrheic dermatitis is a common chronic inflammatory skin condition, characterized by scaling and erythematous patches. It may sometimes be associated with pruritus, and it mainly affects sebum-rich areas, such as the scalp, face, upper chest, and back.

The mildest form of seborrheic dermatitis is commonly referred to as pityriasis capitis, sicca, or dandruff. The sudden onset of severe seborrheic dermatitis should be a red flag for the presence of HIV-AIDS. Common symptoms include redness, scaling, and dandruff. On darker skin, there may be persistent dyschromia with variable hyper/hypo-pigmentation, it is called petaloid seborrheic dermatitis. Other conditions associated with Malassezia may be present, including pityriasis versicolor and folliculitis in adults and neonatal cephalic pustulosis. Lesions on the front of the chest tend to have a psoriasiform morphology but frequently have a petaloid appearance, with such annular lesions commonly observed on the face in darker skin phenotypes. A pityriasiform variation is rare.

There are two types of seborrheic dermatitis:

• Adult seborrheic dermatitis (ASD)

• Infantile seborrheic dermatitis (ISD).

Adult SD:

The face, scalp, and chest are the sites most commonly involved in ASD. On the head and neck, seborrheic dermatitis is mainly symmetrical and involves the central third of the face, including the malar region, the center of the forehead, the eyebrows, the postauricular area, and the external ear canal. It can also affect the nasolabial and alar folds, and blepharitis can also happen with the involvement of the anterior (lash) line.

Infantile SD:

ISD usually appears in the 2nd week of life and can last for 4 to 6 months. Infants do not get troubled by seborrheic dermatitis, but it may cause parental anxiety, often appearing as really firm, greasy scales on the crown and frontal regions of the scalp. It is present in the diaper region, the skin creases of the neck, and the axillae.

Pityriasis amiantacea may be present in ISD. It may occur in young children or older infants but is not specific to seborrheic dermatitis. Typically, there are thick, yellow scales enveloping scalp hairs and binding them in tufts, and can also be present in tinea capitis, scalp psoriasis, and atopic dermatitis.

A common skin condition known as cradle cap (a form of Infantile SD) can also develop on the scalp of the baby. Sorbolene cream and a soft toothbrush can be used to soften and remove the cradle cap scales. On the other hand, it is crucial to relieve itch and discomfort in ASD. 

• Lack of sleep

• Stress

• Vitamin D deficiency

• Disruption of the skin’s microbiota

• Impaired immune reaction to Malassezia.

• The increased presence of unsaturated fatty acids on the skin surface

• Disruption of cutaneous neurotransmitters

• Sunlight and lack of sunlight

• Abnormal shedding of keratinocytes

• Epidermal barrier disturbances associated with genetic factors

• The role of Malassezia also includes the degradation of sebum and consumption of saturated fatty acids, disrupting the lipid balance on the skin surface. 

Risk factors that lead to the development of seborrheic dermatitis include:

• Age 

• Male sex 

• Increased sebaceous gland activity 

• Immunodeficiency, including:
  • Lymphoma
  • Renal transplantation
  • HIV-AID

• Neurological and psychiatric disease, including:
  • Parkinson disease
  • Stroke
  • Alzheimer dementia
  • Major depression
  • Autonomic dysfunction

• Exposure to drug treatment, including:
  • Dopamine antagonists
  • Immunosuppressants
  • Psoralen/PUVA
  • Lithium

Topical antifungals are the first-line treatment for seborrheic dermatitis. Ketoconazole, ciclopirox olamine, bifonazole, zinc pyrithione, piroctone olamine, selenium sulfide, and miconazole are some of the most common topical antifungals that doctors might prescribe.

Clobetasol, clotrimazole, betamethasone dispropionate, hydrocortisone, desonide, fluocinolone, and mometasone furoate are some steroids that your doctor might prescribe. Topical corticosteroids and calcineurin inhibitors should only be used for significant symptoms and to manage moderate to severe flare-ups.

Elidel and protopic are some Immuno-modulators.

Metronidazole gel, soolantra, tretinoin, adapalene (one individual has had success with it), and Lotrimin Ultra (if allergic to clotrimazole, then try this as it contains butenafine, another OTC antifungal) are some other common medicines that your doctor might prescribe.

Calcipotriene is a form of vitamin D that your doctor might prescribe.

Oral medications include itraconazole, fluconazole, and terbinafine.

• When washing your face and hair, try using soft water as hard water can be a trigger for most people with seborrheic dermatitis. Cold water is best to use than hot water.

• You can use skincare products (cleansers, toners, exfoliants, serums, moisturizers, and sunscreen) that are free from Malassezia-promoting ingredients.

• When it comes to oils, MCT oil c8 and c10 (without lauric acid) is the best option. It can be used as a moisturizer.

• Zinc oxide, sulfur, manuka honey, colloidal oatmeal, caprylic acid, squalane oil, ACV, clindamycin, salicylic acid, azelaic acid, niacinamide, dead sea salt, snail mucin, and hypochlorous acid can help with seborrheic dermatitis.

Note: all of these products should be fragrance-free and shouldn’t contain any sulfates and parabens.

• You can shampoo 2 to 4 times a week depending on if you have an oily or dry scalp. Medicated shampoos (Ketoconazole, coal tar, ciclopirox, zinc pyrithione, sulfur, piroctone olamine, or selenium sulfide) can help to deal with seborrheic dermatitis on the scalp, and non-scalp areas (eyebrows, ears or facial hair). You can have 3 different shampoos and make sure to alternate between them. One shampoo can be a strong one to help with bad flares, the second one can be a mild shampoo to help with mild flares, and the last shampoo can be the one you can use to manage your seborrheic dermatitis for when the inflammation, redness, and flakes have gone down (baby shampoos are best).

• You can apply MCT oil c8 and c10 (without lauric acid) on your hair for a few mins before using medicated shampoos.

If the above tips worked but your seborrheic dermatitis hasn’t fully gone away and still comes back, you can try changing your diet.

Since seborrheic dermatitis is caused by Malassezia, you can try taking, probiotics, prebiotics, vitamins, or minerals along with trying out diets like keto or low-carb diets, and cutting out gluten, dairy, spicy foods, eggs, sugar, cinnamon and other similar spices, citrus fruits, nuts, caffeine, and alcohol can help.

• You can change your pillow covers every 3 days to prevent the bacteria from making contact with your skin.

• You can blow-dry your hair after a shower or bath. This helps to prevent flaking.

• Do not use the same shampoo every time (one treatment will not work for seborrheic dermatitis). Try to rotate between 3 or 4 shampoos containing different ingredients.

• Exercising can help.

• A humidifier is another method you can try.

• Taking Vitamin D tablets along with fish oil supplementation in your diet can help.

• Get proper sleep and manage your stress.

This treatment consists of three parts:

1. Destroying the biofilm,
2. Killing the Malassezia, and
3. Rebuilding the skin barrier.

• Ingredients for destroying the biofilm: xylitol, ACV (apple cider vinegar), selenium sulfide, MCT oil without lauric acid
• Ingredients for killing Malassezia: ciclopirox, ketoconazole, coal tar, zinc pyrithione, and MCT oil without lauric acid
• Ingredients for rebuilding the skin barrier: panthenol (vitamin B5), niacinamide (vitamin B3), glycerin, and aloe vera
• Salicylic acid is not anti-fungal, but it’s great at removing the scales, regulating sebum production, and calming down the inflammation.

For example:

On day 1, you can use a shampoo containing selenium sulfide.

On day 3, you can apply MCT oil and then use a shampoo containing ciclopirox, ketoconazole, or zinc pyrithione. After drying your hair, you can use a product containing panthenol (vitamin B5), niacinamide (vitamin B3), glycerin, or aloe vera to repair your skin barrier.

You can do all three parts on a particular day or scatter them throughout the week, depending on whatever suits your schedule and skin needs. You can try experimenting and see what works for you. Once the inflammation, redness, and flakes have gone down, you can use a normal shampoo along with a product (that repairs your skin barrier) to maintain seborrheic dermatitis.

Note: all of these products should be safe from Malassezia-promoting ingredients.

• Toners

• Exfoliators

• Moisturizers

• Sunscreens

Yes, seborrheic dermatitis can cause hair loss because of irritation and inflammation. This results in irritation which in turn causes hair loss or increased hair shedding. Frequent or daily shampooing does not cause hair loss or increased hair shedding. You can prevent hair loss by shampooing every other day (4 times a week). If you have a dry scalp, you can shampoo less.

Yes, individuals with severe seborrheic dermatitis are likely to have severe telogen effluvium.