Psoriasis occurs when the skin cells develop at a more rapid pace than usual. As a result, skin cells build up on each other, which creates a thick, scale-like appearance to the skin.
According to the National Psoriasis Foundation, an estimated 50 percent of people who have psoriasis on their body have it on their scalp.
Most commonly, scalp psoriasis is treated with topical applications, such as shampoos. In this article, we look at the types of shampoos that can treat psoriasis, and which ones might be the best options.
How shampoos can help
Psoriasis shampoos can reduce inflammation and scalp scaling.
Shampoos can work in different ways to reduce the incidence of psoriasis. How they work depends on what ingredients they contain.
Psoriasis shampoos will usually reduce inflammation and scalp scaling.
Doctors often recommend that people regularly change the types of shampoos and other topical treatments they use for their psoriasis. This is because the shampoos become less effective the more they are used.
Examples of ingredients commonly found in shampoos available over-the-counter for scalp psoriasis include:
Salicylic acid is a medication that is applied directly to the affected skin. It helps to treat scalp psoriasis by reducing the incidence of scaling on the scalp.
As a result, a person's psoriasis plaques will soften, and the scales are easier to remove.
Some people who use salicylic acid in psoriasis shampoos find that it irritates their skin, however.
Coal tar shampoo is available in over-the-counter preparations that are derived from coal and wood.
Coal tar contains a compound that helps to reduce the excessive development of skin cells. Additionally, coal tar reduces the symptoms of scalp psoriasis, such as itching and soreness.
More potent coal tar preparations are available by prescription.
How are they used?
After applying the shampoo to the scalp, it is best to leave it on for 5 to 10 minutes then wash it off and reapply.
People who have a sensitive scalp may only be able to apply psoriasis shampoos about twice a week.
Psoriasis shampoos are intended to treat the scalp, not to clean the hair. A person will usually need to use a regular shampoo to wash their hair after using a psoriasis shampoo.
How psoriasis affects the scalp
Psoriasis can cause mild to severe scaling on the scalp.
Psoriasis can result in symptoms that range from mild to severe scaling with crusted plaques on the scalp.
Scalp psoriasis may also extend to a person's forehead, ears, and back of their neck, which can be very uncomfortable.
At first, a person may confuse scalp psoriasis with dandruff because flaking of dead skin cells will occur. However, doctors will often recognize psoriasis by its scaly, silver appearance.
Other symptoms associated with scalp psoriasis include:
- bleeding, which is most often a side effect of scratching the scalp
- dry scalp, which may result in cracking and bleeding or itching, which may interfere with a person's ability to get a good night's rest
- soreness due to the skin scaling and as a result of itching
- hair loss, due to repeated itching or severe scaling on the scalp.
Even when scalp psoriasis does cause hair loss, the hair loss is rarely permanent.
While most people with scalp psoriasis know they should not scratch their scalp when it itches, the desire to do so can be overwhelming. However, doing so can worsen symptoms and cause the areas of psoriasis to grow or become infected.
When to see a doctor
If topical treatments do not have the desired effect, visit a doctor.
Unfortunately, scalp psoriasis can be difficult to treat, and it is hard to predict what treatments will be effective.
If over-the-counter shampoos or medicated shampoos do not relieve a person's symptoms, they should see a doctor.
This is particularly important when scalp psoriasis causes cracking or bleeding, as it is possible that the skin and scalp could become infected.
Other treatment options
Over-the-counter scalp shampoos are not the only way to treat scalp psoriasis.
Other options include treatments that a person can apply to the scalp and leave for a short time, sometimes overnight.
Examples of these include:
- Topical steroids as a gel, lotion, or foam: These can reduce the itching and redness associated with scalp inflammation. However, they do not tend to help with scaling as well as coal tar and salicylic acid shampoos do.
- Coconut oil compounds: These combine coal tar, salicylic acid, and sulfur with coconut oil, which softens skin plaques. Coconut oil compounds work best when they rubbed into the scalp, left on overnight, and washed off in the morning.
- Dithranol: A plant-based treatment that people have used for more than a century to treat the condition. While it is effective in treating psoriasis, it can stain hair and skin. As a result, it is not used as commonly to treat scalp psoriasis.
These creams, gels, lotions, or ointments work to slow down or normalize excessive cell reproduction and reduce psoriasis inflammation. Some of the more common medications include:
- Dovonex (calcipotriene)
- Taclonex (calcipotriene and betamethasone dipropionate)
- Tazorac (tazarotene)
- Clobex (clobetasol propionate)
If scalp psoriasis does not improve after using these topical treatments, a doctor may recommend phototherapy, in which ultraviolet rays are used on the scalp.
Laser ultraviolet B (UVB) treatments are the latest advance in the treatment of scalp psoriasis. Lasers can be targeted precisely to psoriasis lesions, allowing people to withstand higher doses of UVB light. There are also fewer side effects than with medications.
Doctors may also prescribe biologics, which work in the body to reduce inflammation.
While oral medications are available, they may not be as effective as shampoos when it comes to treating scalp psoriasis.
People with scalp psoriasis tend to experience periods where their symptoms worsen, followed by times where the symptoms improve or go away.
According to the Psoriasis and Psoriatic Arthritis Alliance, a person may have to apply psoriasis shampoo for up to 8 weeks before the psoriasis plaques will start to reduce.
Sometimes, a person will need apply a psoriasis shampoo every 2 to 3 weeks in order to keep scalp psoriasis at bay.