Seborrheic Dermatitis (Seborrhea)
What Causes Seborrheic Dermatitis?
Surprisingly, no one is quite sure what causes seborrheic dermatitis—or at least not everyone agrees on the cause. It's thought to be caused by the overproduction of sebum (oil), combined with irritation from a naturally-occurring yeast, Malassezia. It seems that the yeast itself isn't the problem; rather, it's components of this yeast that generate inflammatory fatty acids that trigger seborrheic dermatitis.
There are also a number of potential secondary factors that play a role in causing seborrheic dermatitis. These include family history, stress, weight (the heavier you are the more likely you are to have flare-ups), weather, and other health issues, especially autoimmune disorders.
Age is also a factor in seborrheic dermatitis: It's often seen in infants 3 months or younger, and in adults between the ages of 30 and 60.
Research has revealed that having acne or rosacea increases a person's risk for seborrheic dermatitis. That's not surprising, as both acne and rosacea are inflammatory disorders.
What Does Seborrheic Dermatitis Look Like?
Seborrheic dermatitis often appears as mild red patches, often with greasy scales, which can appear almost anywhere on the body, but most often occur on the scalp (where it's commonly known as dandruff) and on the sides of the nose. It's believed that about 5% of adults have this condition.
Seborrheic dermatitis also occurs commonly in infants; parents notice thick, oily scales on a child's scalp, eyebrows, behind the ears, or on the chest. Infant seborrheic dermatitis (commonly known as cradle cap) differs from other forms of the condition in that it is only temporary. Babies can have recurrences of cradle cap, but in most cases it goes away on its own, or with mild treatment (such as medicated shampoos). Why exactly it eventually disappears in infants is unknown.
Medical Treatments for Seborrheic Dermatitis
Seborrheic dermatitis is difficult to treat. What clears it up in one person might not work for another, so there's a lot of trial and error involved in finding the right fix for you. Although this is frustrating, it's important not to give up; the next treatment you try could be the one that works!
The first step is to see a dermatologist to determine if what you have is truly seborrheic dermatitis. Once you have a diagnosis and know exactly what you're dealing with, it's much easier to devise a plan of attack. Following are the chief medical options available to get seborrheic dermatitis under control:
- Topical antifungal agents, such as ketoconazole (available by prescription and included in some medicated over-the-counter shampoos such as Nizoral).
- Creams or lotions containing corticosteroids (both over-the-counter and prescription strength) can reduce the inflammation that's part of this condition.
- Topical immunomodulators (medications that suppress or alter the immune system), such as pimecrolimus, can calm overactive oil glands and reduce the amount of sebum they produce.
If you opt for corticosteroids, a physician can help determine the best strength for you. If it's too weak it might not have much of an impact, while if it's too strong it can have side effects such as burning, irritation, and, with ongoing use, thinning of the skin. You may need to alternate prescription strength treatments and over-the-counter strength treatments.
There is still much ongoing research to determine the best course of action to treat seborrheic dermatitis. Be sure to find a dermatologist you trust and who you can speak openly with about how your seborrhea is doing, and don't be afraid to ask if there are any new treatments available! If a treatment protocol your dermatologist has advised isn't working— speak up! It's likely that there is something else to consider. Don't assume that what your dermatologist first prescribed is your only option.
Skin Care to Help Seborrheic Dermatitis
The way you treat your skin can have a big impact on the severity of your seborrheic dermatitis, and even can keep the condition under control. Using gentle, water-soluble cleansers with a soft washcloth can help a lot, as these remove excess surface oil and help remove dead skin cells.
When not using medication on your scalp and body, be sure to use very gentle products that won't dry out or irritate your skin. When washing your hair, massage the scalp to remove any scales, then rinse thoroughly. When you apply conditioner, take care to apply it only to your hair, and not to your scalp, as conditioner has emollient ingredients that can cause skin cells to build up and prevent shedding.
Avoid alcohol* in products you use on your face and body. Although alcohol does degrease oily skin, it is so drying and irritating that it actually triggers increased oil production, which is the last thing you need if you're suffering from seborrheic dermatitis. There are many good cleansers, toners, and moisturizers out there that don't include harmful alcohol (you can find them in our Best Products section).
*The alcohols to be concerned about in skin-care products are ethanol, denatured alcohol, ethyl alcohol, methanol, benzyl alcohol (when it's one of the main ingredients), isopropyl alcohol, and SD alcohol, all of which can be extremely drying and irritating to skin, and are capable of generating free-radical damage and disrupting the skin's protective barrier.
Perhaps most important is using a well-formulated, gentle BHA (salicylic acid) exfoliant to reduce the redness and flaking caused by seborrheic dermatitis. You can use a BHA exfoliant once or twice daily (after cleansing and toning) on your face, body, and scalp to reduce the most telltale signs of the problem.
Along with gentle skin care and a well-formulated BHA exfoliant, you also can consider a topical treatment product known as DermaZinc. Although difficult to find in stores, you can order it from reputable online retailers. This unique product is medicated with zinc pyrithione, an anti-dandruff ingredient that's believed to reduce the proliferation of the yeast that contributes to seborrheic dermatitis.
Although seborrheic dermatitis can be a chronic, frustrating condition, it's certainly not one that you must just tolerate! Armed with the right tools (and perhaps a visit to the dermatologist), you can fight back and look and feel great.
Sources: Acta Dermatovenerol Croat 2012, 20(2):98–104; Bolognia, Jean L., ed., Dermatology, pp. 215–218, New York: Mosby, 2003; Freedberg, Irwin M., ed., Fitzpatrick's Dermatology in General Medicine, 6th ed., pp. 1198, 1200, 1374, New York: McGraw-Hill, 2003; Habif, T. P , ed., Clinical Dermatology, 5th ed., Philadelphia: Mosby Elsevier, 2009; Paddock, Mike, March 4, 2011, "What Is Cradle Cap? What Causes Cradle Cap?" Medical News Today; Mycopathologica, December 2006, pages 395–400; Journal of Investigative Dermatology Symposium Proceedings, December 2005, pages 295–297; and The Mayo Clinic.