Wondering about those itchy, scaly patches on your scalp and whether there's anything you can do about them?
Don't fret. You might be experiencing psoriasis on your scalp and, yes, there are ways to treat it.
Why do people get scalp psoriasis?
"We don't know why some people get it on the scalp and some don't," Adam Friedman, MD, professor of dermatology at George Washington School of Medicine and Health Sciences, tells Health.
He explains that while it's not known exactly what causes plaque psoriasis, a combination of genetic makeup and environmental factors are believed to be involved.
While skin cells usually grow and fall off in a month's cycle, the skin cells of those with plaque psoriasis grow faster, due to an overactive immune system. The skin cells tend to grow in about three to four days, yet they don't fall off at the same pace, leaving dead skin cells to buildup on the skin.
While there isn't a known reason for why people get psoriasis on different parts of the body, Dr. Friedman says he finds that those with scalp psoriasis also get inverse psoriasis, which occurs on the folds of skin like the groin and underarms. He notes that because those areas can be moist, psoriasis might look different.
"So, people who have this are often underdiagnosed because it doesn't have that classic appearance. In the groin area, it can be assumed it's a yeast infection or sexually transmitted disease. This is why it's important to make a correct diagnosis," Dr. Friedman says.
Robert T. Brodell, MD, chair of the department of dermatology at the University of Mississippi Medical Center, adds that many of his patients with scalp psoriasis also have it on their elbows and knees, as well as experience pitting in their fingernails.
"I do also have patients with it only the elbows or only the knees or only on the scalp. So, it's a mixed bag," he tells Health.
What are the symptoms of scalp psoriasis?
Symptoms of psoriasis on the scalp might include:
- Fine scaling that looks like dandruff, or appears as thick, crusted plaques on the scalp
- Red, itchy areas on the scalp
- Scaling that covers parts of the scalp or the entire scalp
- Scaling that may extend beyond the hairline onto the neck
"It can be itchy and painful and all that together can make psoriasis that affects a small body area disabling," says Dr. Friedman.
Scalp psoriasis can have a social impact, too, he adds.
"If someone sees a person with a flaky, red scalp, they may assume the person is unkempt or has a fungal infection, so there is an added level of anxiety associated with that in terms of misunderstanding what scalp psoriasis is and punishing the patients," Dr. Friedman says.
How does psoriasis affect the scalp and the hair?
"Even a little inflammation can cause hair loss," Dr. Friedman points out. "Hair is very fickle, it's a prima donna, so to speak; it wants a perfect environment to grow."
Hair is so fickle, he notes, that even dandruff can cause hair loss.
While the AAD says hair often grows back once psoriasis clears on the scalp, it recommends ways to help prevent further hair loss, such as gently combing and brushing away scales, avoiding picking off scales, and letting your hair air dry.
How is scalp psoriasis treated?
There are several options for treating scalp psoriasis, and your dermatologist may use one or a combination of the following to find what works best for you.
First-line therapy for plaque psoriasis on any part of the body is a topical anti-inflammatory, says Dr. Friedman. The NPF says that topical treatments include medicated shampoos, steroids and tars, and prescription topicals.
"The tricky part is that using an ointment or cream on the scalp can be difficult; think about applying an ointment or cream in a hairy area, that's not easy," he says.
In some cases, he says, foam, liquids, or gels are better options for the scalp. However, he adds that some of his patients who have brittle or dry hair like using ointment on the scalp.
Some topical options are available over-the-counter (OTC). The NPF recommends looking for the following active ingredients:
- Salicylic acid, which softens plaques and scales and removes them from the skin.
- Tar (made from coal or wood), which slows skin cell growth and reduces inflammation, itching, and scaling.
Before buying OTC products, NPF recommends looking at its Seal of Recognition program, which includes products that aim to be non-irritating and safe for people with psoriasis.
Phototherapy shines ultraviolet (UV) rays on the skin with the intention of slowing skin-cell growth. According to the AAD, it can also suppress an overactive immune system, reduce inflammation, and relieve itchiness so that the skin can heal.
A dermatologist may use a handheld device, which looks much like a blow dryer, to treat scalp psoriasis, says AAD.
The downside of phototherapy? "While it works well, some patients find it hard to go into an office three times a week for light therapy," says Dr. Friedman.
If topicals or UV light therapy do not help your scalp psoriasis, your doctor may prescribe medicines or biologics.
There are several types of oral medications that doctors may prescribe to improve psoriasis symptoms. These drugs work by slowing down the immune system and include medicines like methotrexate, apremilast (Otezla) and tofacitinib (Xeljanz), but there are many others, says the NPF.
Biologic medications, which are delivered by injection of IV infusion, target specific parts of the immune system. Again, per the NPF, there are a variety from which to choose, including as adalimumab (Humira), ustekinumab (Stelara), and secukinumab (Cosentyx) and others.
Dr. Friedman often prescribes systemic agents for scalp psoriasis because he finds them more effective than topical options for the scalp and because those with scalp psoriasis have a three-fold increased risk for developing psoriatic arthritis.
"And you're not going to treat arthritis with a topical. But I am quick to have a discussion with patients that when it comes to treatment, it's not one or the other. They can make a good decision based on all the information available," says Dr. Friedman.
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