Seborrheic dermatitis and hair loss can both occur on the scalp in the same place– but is seborrheic dermatitis causing the hair to fall out?
Seborrheic dermatitis, also known as dandruff, is a common scalp condition. As it is on the scalp, it is not uncommon to find both hair loss and seborrheic dermatitis together. But when someone has alopecia, the medical term for hair loss, and seborrheic dermatitis together, is the rash the cause of the reduced hair?
What is seborrheic dermatitis?
Seborrheic dermatitis is a rash that starts with overgrowth of yeast of the Malassezia group, which naturally live on oily areas of human skin, which sets off an inflammatory response. Compromise of the skin barrier may also trigger the condition. It a chronic, recurrent condition that tends to flare up seasonally especially in the spring, fall and when the weather is very cold. Occurring most commonly on the scalp, seborrheic dermatitis, however, can also affect other parts of the body such as the t-zone of the face, bearded areas, ears, chest, upper back, armpits and genitals.
When does seborrheic dermatitis appear?
Seborrheic dermatitis is a condition usually seen post puberty when hormonal changes trigger increased sebum (skin oil) that supports yeast that live on the skin. The condition, however, also occurs in newborns who may also have high sebum production due to exposure to maternal hormones. The condition in babies is called cradle cap. Cradle cap tends to resolve in a few weeks. Seborrheic dermatitis tends to not occur again until puberty when hormonal changes increase sebum which feed the yeast.
Read: Can fibroids cause hair loss?
What does seborrheic dermatitis look like on the scalp?
In addition to the flakes of dandruff in the hair, the rash of seborrheic dermatitis is characterized by itch, scale, flaking, redness and discoloration– most commonly on the frontal hair line when on the scalp. Some use the term dry scalp to describe the condition because of the flakes and crust. The scalp, however, isn’t dry but inflamed. It occurs on oilier parts of the body. In more severe cases seborrheic dermatitis on the scalp causes scabs and even bleeding. Sometimes there are no visible changes but there is itching.
How seborrheic dermatitis causes hair loss
- itch caused by seborrheic dermatitis can cause a person to vigorously scratch a hairy area. Scratching can cause hair breakage and loss. Treat the hair loss by treating the seborrheic dermatitis.
- Seborrheic dermatitis is an inflammatory skin condition. Severe inflammation can cause damage to the scalp skin and hair follicles leading to hair loss. If inflammation is severe this could potentially cause scarring, however, this is rare. Background inflammation in even mild case of dandruff or seborrheic dermatitis can exacerbate other types of hair loss.
irritant contact dermatitis
- Seborrheic dermatitis compromises the skin barrier function on the scalp. This means that when someone is experiencing a seborrheic dermatitis flare up, they may not be able to tolerate products when applied to the scalp because of irritation. Irritation increases inflammation which, as stated above, can cause hair loss
Seborrheic dermatitis treatments for scalp
Regardless of whether seborrheic dermatitis is causing hair loss, it’s important to treat it. The condition is itchy. It puts a person at risk of irritant to hair care products and treatments. Seborrheic dermatitis also can discolor the skin.
Shampoo for seborrheic dermatitis
For those who suffer with seborrheic dermatitis it is important to shampoo at least weekly. Build up of dead skin cells and oil cause inflammation on their own and by supporting overgrowth of yeast. Some people shampoo less frequently because they want to maintain certain hair styles. In this case they may be able to manage the condition with less frequent washing if they use a dandruff shampoo and/or a medication such as a topical steroid.
Common ingredients in dandruff shampoos include:
- zinc pyrithione
- selenium sulfide
- salicylic acid
- tea tree oil
Topical steroid for seborrheic dermatitis
Topical steroid for seborrheic dermatitis treatment is a great way to get control of flare ups. Steroids calm down the inflammatory reaction which reduces symptoms and scaling. In general, steroids should be used for only two weeks to avoid atrophy or skin thinning. In cases in which treatment must go on for longer, sometimes antifungal agents or calcineurin inhibitors such as tacrolimus ointment or pimecrolimus cream can keep the condition under control. Again, if control of seborrheic dermatitis is an issue, make best efforts to shampoo weekly to remove the build up that triggers flares.
Are all scalp rashes seborrheic dermatitis?
Sometimes it is difficult to know if a scalp rash is seborrheic dermatitis or something else. There are other conditions that cause itching, redness and scale on this part of the body. Some of these also cause hair loss:
- seborrheic dermatitis vs psoriasis– unlike the scale of seborrheic dermatitis which tends to be greasy and yellow, psoriasis creates a silvery scale
- seborrheic dermatitis vs eczema– eczema on the scalp, vs seborrheic dermatitis, tends to favor the back and commonly extends down the neck. There is generally more lichenification (skin thickening) than scale
- seborrheic dermatitis vs ringworm – also known as tinea capitis is a fungal infection of the scalp which also causes hair loss. Ringworm is more common in prepubescent children, unlike seborrheic dermatitis. In children is is important to screen for a fungal infection when there are patches of hair loss, itch and scale on the scalp.
- seborrheic dermatitis vs scarring hair loss– Some other conditions of the scalp that also can cause redness, itching, scaling with hair loss are cicatricial alopecias, or scarring hair loss. These include central centrifugal cicatricial alopecia, discoid lupus, and lichen planopilaris.
Is seborrheic dermatitis hair loss permanent?
Although seborrheic dermatitis can be severe, as can be its associated hair loss, when the condition is successfully treated, the good news is that hair usually grows back normally.
So can seborrehic dermatitis cause hair loss? Usually it’s just a coincidence when seborrheic dermatitis and hair loss occur together. Seborrheic dermatitis is common. In severe cases, however, seborrheic dermatitis can hair to common out in a common location if there is enough scratching or severe inflammation. It may also worsen other types of alopecia. This is why it’s important to see a hair loss dermatologist for these types of problems.
Got hair loss? Have a scalp problem? Looking for a hair loss doctor? Make an appointment with our expert hair loss dermatologist at 212-627-1004 or here.
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