Scalp Psoriasis or Dandruff? Understanding the Differences

When students are in medical school, they’re generally taught “when you hear hoofbeats, think horses, not zebras.” Translation? When considering symptoms, reach for the most common diagnosis rather than the more obscure. So, if you develop a problem with an itchy, flaky scalp, it’s natural to think dandruff rather than scalp psoriasis.  

After all, dandruff affects about one in two people (roughly 50 million people in the U.S. alone), while scalp psoriasis affects about one in two people who have psoriasis (that’s about 3.25 million).  

However, it’s critical to distinguish between the two. The reason: Scalp psoriasis is just one external manifestation of psoriasis, a chronic inflammatory condition that causes an overgrowth of skin cells resulting from a glitch in the immune system. And that’s not all. 

“When we see the skin inflamed, we know the body inside is inflamed,” explains Rachna Bandhari, MD, PhD, a board-certified dermatologist at the Bucay Center for Dermatology and Aesthetics in San Antonio, TX. And researchers now know that that internal inflammation can be linked to a host of problems. In fact, studies show that psoriasis is associated with a higher risk of heart disease, psoriatic arthritis, hypertension, obesity, and diabetes. 

Fortunately, recognizing and treating scalp psoriasis can not only relieve scalp symptoms but also help protect you from the related conditions listed above. 

What Are the Signs of Scalp Psoriasis?

Scalp psoriasis is marked by patches — also called plaques — of scaly skin not only on the scalp itself but also around its margins. For example, one of the first signs of scalp psoriasis noted by Beth M., a 44-year-old from Vermont, was a patch of red, scaly skin on her forehead, so it took a while for her to realize it was actually scalp psoriasis.  

Other areas that may be affected include the skin behind and inside the ears and on the neck. In addition, says Dr. Bandhari, you may experience “scaling, flaking, itching, discomfort, and pain.” Severe cases can even lead to temporary hair loss. 

The plaques also range in color, depending on your skin tone. People with lighter skin tend to develop red or pinkish plaques with silvery scales, while people of color may experience purple, violet, and brown plaques with gray scales. The severity of your scalp psoriasis may also affect how it looks. For example, in milder cases, it may look like a gentle scaling with dandruff-like flakes. In more severe cases, the plaques become thicker and more discolored with better defined margins.  

Scalp Psoriasis vs. Dandruff

The fact is, it can be confusing to tell dandruff apart from scalp psoriasis. As Dr. Bandhari explains, they exist on a spectrum of scalp disorders, so overlap of symptoms is not unusual.  

What they have in common are flakes, itchiness, and dryness. Where they differ? Scalp psoriasis also comes with symptoms like pain, burning, redness, thick plaques with a silvery or grayish sheen, bleeding and even temporary hair loss.

What’s more, people with scalp psoriasis usually have plaques elsewhere on the body, such as the elbows and knees, and may have other psoriasis symptoms such as nail pitting.  

And while scalp psoriasis is a chronic inflammatory disease that can have widespread effects in the body, as explained above, “with dandruff, the culprit is a yeast overgrowth,” explains Dr. Bandhari, and it doesn’t pose any additional harm to the body. While dandruff often responds to over-the-counter anti-dandruff shampoos, scalp psoriasis will not — which is a clue that a flaky scalp requires medical attention. 

What Are Scalp Psoriasis Triggers?

“In general, scalp psoriasis is an inflammatory condition, and stress can be a trigger in itself,” says Dr. Bandhari. So anything you can do to minimize tension and anxiety — e.g., crafting, yoga, meditation, relaxation techniques and so on — may help prevent flares. 

Although diet has yet to be study-proven to be a trigger, Dr. Bandhari advises her patients to “watch what inflammatory foods you’re eating, such as dairy, gluten, and sugar.” While the jury is out, it can’t hurt to pay attention to how foods may affect your scalp by keeping a food log. 

Not scratching or picking scales may be a challenge when you have scalp psoriasis, yet any sort of “trauma” to the scalp can bring on the Koebner phenomenon — i.e., a psoriasis flare in response to injury.  

By the same token, avoid vigorously brushing your hair, and when you shampoo and condition, be gentle. To avoid irritating her scalp, Diane Talbert, a Black woman who has been living with scalp psoriasis for 60 years, says, “I don’t do perms, chemicals, and no straightening products, including straightening combs.”  

Dr. Bandhari adds that it’s smart to avoid hairstyles that put pressure on the scalp — e.g., braids, updos, and other styles that involve tugging and/or tightly securing the hair. Beth says, “I keep my hair long enough to cover the psoriasis but short enough to easily wash and manage.” Also, avoid curling and straightening irons, and if you blow dry, use the coolest setting. 

Environmental factors such as sunburn and cold, dry weather can also trigger a flare, as may lifestyle habits such as smoking and drinking alcohol. Try tracking your symptoms to understand what might be causing your scalp psoriasis to act up. 

How Can You Treat Scalp Psoriasis?

The good news is that while there is no cure for scalp psoriasis, it can be well-controlled thanks to a wide array of treatment options now available. Finding the strategy that works for you will likely be a matter of trial and error, which is why Dr. Bandhari urges patience. “If one thing doesn’t work for you, don’t despair.” 

Here is an overview of treatments now available: 

Over-the-counter products

Medicated shampoos, creams, gels, lotions, foams, ointments, and soaps containing ingredients such as salicylic acid, coal tar, zinc pyrithione, or selenium sulfide may help reduce flaking, ease redness and soreness, and soften scales. Note: Many of these products are available in stronger prescription-strength formulas. 

Steroids

Usually, the first line of prescription treatment, these are available in ointment, lotion, cream, gel, foam, spray, and shampoo forms. It’s important to apply to the scalp, not the hair, to get the full benefit, which includes reduced inflammation, redness, itching, and scales. Also, discuss your shampoo routine with your dermatologist, so they can take that into account when planning your treatment. “There’s no need to change the frequency of your shampooing,” says Dr. Bandhari. “Use your regular routine.” Note: Steroids may also be injected into the scalp to treat discrete patches of scalp psoriasis. 

Vitamin D analogues

A synthetic form of vitamin D available in cream, ointment, and foam form, vitamin D analogues (e.g., calcipotriene) can help ease inflammation, remove scales, and slow skin growth. Apply to scalp at bedtime, cover with a shower cap, and allow the medication to penetrate the plaques overnight.  

Light therapy

When your scalp psoriasis doesn’t respond to topical treatments, your dermatologist may recommend light therapy, also known as phototherapy, which can help slow the growth of excess skin cells and reduce the formation of plaques. Treatments involve exposing the skin to ultraviolet light either in the doctor’s office or at home, using a special unit. 

Systemic treatments

In severe cases of scalp psoriasis, systemic — e.g., bodywide — treatments — may bring relief by addressing the underlying inflammation caused by psoriasis. Oral options include disease-modifying antirheumatic drugs (DMARDs) like methotrexate, immunosuppressants like cyclosporine and newer treatments like PDE4 inhibitors, which target enzymes that cause inflammation in the first place. You may also benefit from biologic treatments, given by injection or infusion, that block immune cells from causing rapid skin growth and inflammation. 

Home Remedies for Scalp Psoriasis

Various home remedies, such as aloe vera creams and avocado oil, can help relieve the itching and inflammation of scalp psoriasis and also loosen scales, but they should always be used as a complement to the treatments prescribed by your dermatologist.  

“Some people like tea tree oils, others love coconut oil,” says Dr. Bandhari. “Everybody has to try what works for them.” For example, Diane says coconut and avocado oil “help with the flakes.” To use, Dr. Bandhari says, “Gently massage a few drops of oil into the scalp once a week, cover with a shower cap, and keep on at least 20 minutes or even overnight.” Rinse out and shampoo and usual. 

Do-it-yourself scrubs can also bring relief from itching and inflammation. Try making a paste with either Epsom salts or uncooked oatmeal, water, and a little olive oil. Apply to the scalp, let sit for 10 minutes or so, then wash hair as usual. And while some people swear by solutions made with apple cider vinegar and capsaicin, tread carefully — they can sting and irritate scalps that are cracked or bleeding. 

Join GHLF’s HEROES Program

GHLF invites you to make a difference in your community with our FREE and unique program called HEROES (Health Education + Reliable Outreach + Empathetic Support). HEROES is a FREE education and outreach initiative that equips beauty professionals to better support clients living with scalp and other skin conditions and offers people living with skin and scalp conditions helpful resources and information on getting a proper diagnosis, managing symptoms, and becoming an empowered patient. To learn more, visit GHLF.org/HEROES today.