The condition affects over 7.5 million Americans.
When psoriasis affects the scalp, red, raised, scaly patches appear, and hair loss may occur. Scalp psoriasis can be limited to one or two patches, or it can be widespread. It may affect the whole scalp, the forehead, the back of the neck, or behind the ears.
Psoriasis and scalp psoriasis
Scalp psoriasis may be confused with dandruff due to flaking skin.
Psoriasis is an autoimmune disorder that causes skin cells to grow too quickly, resulting in scaling and inflamed skin. Scalp psoriasis can lead to hair loss.
When skin cells grow, they form deep within the skin and slowly move to the surface. There, they replace dead cells, and the dead skin is shed. This process normally takes around a month.
Psoriasis speeds up this process. It takes only a few days for new cells to form and rise to the surface. The speed at which this happens causes the skin to build up in patches on the surface.
This buildup of skin is known as plaque.
As the skin builds up, patches of red, thickened skin with silver streaks form. These patches may be itchy or painful. There may be dried, cracked skin that bleeds, and swelling and stiffness in the joints.
In scalp psoriasis, these patches affect the skin of the head. Other locations in which they can appear include the elbows, knees, face, hands, and other areas.
Scalp psoriasis is a kind of plaque psoriasis, but other kinds of psoriasis can affect the scalp. There may be intense itching. Scratching can then cause skin damage.
In addition to the usual symptoms of psoriasis, scalp psoriasis has its own set of symptoms.
- Red patches on the scalp, ranging from barely noticeable to very pronounced and inflamed
- Flaking and scales that may at first resemble dandruff but are accompanied by a silvery sheen
- Dry scalp that may crack and bleed
- Itching that can range from a mild annoyance to an extreme itch that interferes with life and sleep
- Bleeding is common because the skin becomes dry and cracked, and is worsened by scratching
- Burning, soreness, or pain on the scalp
- Temporary hair loss can happen as a result of scratching the scalp or removing the scales
Fortunately, once the outbreak clears, hair generally regrows.
Hair loss prevention and treatment
Injections may help to treat hair loss.
Preventing an outbreak of scalp psoriasis before it starts is the best way to avoid hair loss. Proper treatment is crucial to prevention, and a dermatologist can provide medical treatment that can clear up an outbreak quickly.
- Corticosteroids applied directly to the outbreak to decrease inflammation and itching
- Topically applied vitamin D cream
- Light therapy, though this may not be as effective for some due to hair thickness
- Oral medications including biologics, methotrexate, or retinoids
Medicated shampoos, containing salicylic acid or coal tar, may help. However, shampoo with salicylic acid can also lead to further breakage, since the acid may weaken hair follicles.
Some home remedies and lifestyle changes can help people to take control of their condition and prevent outbreaks.
- Quitting smoking
- Avoiding alcohol
- Limiting exposure to cold weather
- Trying to avoid scratching
- Shampooing gently to avoid further irritation
- Limiting stress
- Maintaining a healthy body weight
Causes, risk factors, and triggers
Cold weather and stress may trigger a psoriasis outbreak.
While the cause of psoriasis remains unclear, it is thought to be linked to a problem with the immune system.
White blood cells known as T cells are thought to attack healthy skin cells. Normally, T cells fight off bacteria and viruses.
These overactive T cells may lead to an excessive production of skin cells. This speeds up the cycle of skin moving to the surface.
A variety of biological and external triggers may start up the cycle. Once it starts, it will not stop without treatment. There are some risk factors and triggers for psoriasis. Knowing these can help to avoid outbreaks and prompt patients to seek treatment sooner.
Risk factors for having the disease include:
- Family history of psoriasis
- Certain viral and bacterial infections such as HIV and recurrent strep throat
- Weakened immune system
External factors that may trigger psoriasis outbreaks include:
- Skin injuries like cuts, scrapes, insect bites, or sunburn
- Cold weather
- Excessive alcohol consumption
- Certain medications such as beta-blockers and medications for bipolar disorder
Psoriasis can involve a number of complications, either medical or impacting quality of life.
Medical complications include:
- Psoriatic arthritis, with painful damage to the joints
- Metabolic syndrome
- Eye diseases like conjunctivitis
- High blood pressure
- Heart disease
- Parkinson's disease
- Kidney disease
- Other autoimmune disorders including Crohn's disease, celiac, and inflammatory bowel disease
Quality of life can be affected by:
- Sleep disruption due to itching
- Feelings of grief or embarrassment over hair loss and skin patches
- Low self-esteem
- Problems at work or school
- Social isolation
Other skin conditions linked to hair loss
Scalp psoriasis is not the only skin condition that may cause hair loss.
To diagnose scalp psoriasis and rules out other possible causes, a doctor can examine a skin sample under a microscope.
Conditions with similar symptoms include ringworm. If the parasite takes up residence in the scalp, this can lead to itching and hair loss.
Several diseases lead to a condition called scarring alopecia, which is hair loss accompanied by scarring. These include some types of lupus, cellulitis, or folliculitis. They account for very few cases of hair loss.