It is often accompanied by itchy, red, and sometimes inflamed skin that is typical of different kinds of eczema.
The type of eczema that most often affects the scalp is called seborrheic dermatitis. In babies, it is known as cradle cap.
Scalp eczema can be a stubborn condition that persists for years. It can come and go without warning, and it can disappear on its own. Symptoms of scalp eczema can be effectively managed, but the condition cannot be cured completely.
In this article, we will examine the risk factors linked to scalp eczema, how to help prevent it, and what to do about it when it occurs.
Risk factors and triggers
Scalp eczema may be triggered by stress, hormones, and illness.
No one really knows what causes scalp eczema, but it affects up to 5 percent of the general population. Slightly more men are affected than women.
Genes, hormones, illness, and stress have all been known to trigger scalp eczema in some people.
Other medical conditions can make people more prone to scalp eczema. These include:
- diseases that weaken the body's immune system or nervous system, including HIV and Parkinson's disease
- skin conditions, such as psoriasis, rosacea, or acne
- allergies, such as asthma and hay fever
- other types of eczema
Other risk factors linked to scalp eczema include the following:
- lack of sleep
- cold, dry weather
- dry skin
- greasy hair
Eczema vs. dandruff
Once triggered, scalp eczema can be made worse by a combination of otherwise normal skin properties.
Naturally occurring oil called sebum, yeast that lives on the skin, and a skin fungus called Malassezia, all play a role.
Sebum is a waxy, fatty substance that is expelled by the sebaceous glands. Too much of this can cause greasy scales to develop on the scalp. This can then cause the overgrowth of an otherwise normal skin fungus called Malassezia.
Dandruff occurs when the Malassezia fungus irritates the sebaceous glands of the scalp. This triggers the body's immune response and causes the distinctive scaly rash.
In short, dandruff is just one symptom of scalp eczema.
Scalp eczema causes patches of skin to become red, flaky, and itchy. It can also affect other oily areas of the body, such as the face, nose, eyebrows, and eyelids.
This form of eczema can also affect the ear canal. When it does, it may result in the discharge of fluid from the ear.
Scalp eczema can cause the skin to become greasy, waxy, or even blistered. These patches of skin can become infected and will release clear fluid.
The color of the skin can change in the affected area, even after it has healed.
Shampoos may be the most effective treatment against scalp eczema.
Although scalp eczema cannot be cured, medical treatment can bring relief by removing the scaly buildup and reducing itchiness.
Treatments for scalp eczema usually come in the form of a shampoo or a cream or gel to apply to the scalp.
Shampoos that are most effective against scalp eczema include those that contain one or more of the following ingredients:
- zinc pyrithione
- salicylic acid
- selenium sulfide
- coal tar
In mild cases of scalp eczema, antifungal creams, ointments, or sprays can be effective. Typically, these contain coal tar or corticosteroids that help calm the irritation and stop the flaking.
In more severe cases, a mild corticosteroid can calm the inflammation. Doctors may prescribe topical corticosteroids to treat an active flare-up marked by redness, itching, and flaking. Corticosteroids are not suitable for use over long periods.
Doctors may also prescribe non-corticosteroid medicine, such as topical drugs that suppress the immune system called calcineurin inhibitors. People can use these for a more extended period than corticosteroids.
In very severe cases, a doctor may prescribe an oral antifungal medication.
Anecdotally, natural remedies have helped relieve the symptoms of scalp eczema in some people. These include the following topical treatments:
- tea tree oil
- olive oil
- aloe vera
The following dietary supplements have been beneficial in some cases:
A physical examination is usually necessary for a doctor to diagnose scalp eczema.
Scalp eczema can cause extreme discomfort, anxiety, and infected skin. When any of these things happen, or if scalp eczema persists despite home treatment, it is usually time to see a doctor.
There is no single test for decisively diagnosing scalp eczema. This is because the yeasts and fungus that play a role in scalp eczema occur naturally on the scalp of everyone.
A doctor will usually diagnose seborrheic dermatitis after a physical examination of the affected skin. They will aim to rule out other similar skin conditions, such as psoriasis and allergic reactions.
Some doctors may refer people to a dermatologist, a doctor who specializes in skin conditions.
The doctor may take a skin scraping to determine whether a fungal infection is also present. Rarely, a small sample may be required to rule out the other conditions that resemble scalp eczema.
Flare-ups can be prevented by reducing stress and by avoiding exposure to suspected irritants. Irritants affect people differently, but they can include hair dye, harsh soap, and very hot water.
It can help to keep the scalp clean with a gentle shampoo and warm water. It is a good idea to do this after heavy work or exercise, as sweat can be a trigger in some cases.
In adults, scalp eczema tends to start during late adolescence. It most often affects adults between the ages of 30 and 60.
In some cases, scalp eczema can clear up without treatment. More often, it lasts for years, and comes and goes without warning. Treatment is often necessary to control the itchy and scaly symptoms.