Psoriasis, an autoimmune disease, affects about 7.5 million people in the United States.
Psoriasis is a disease that causes plaques, which are itchy or sore patches of thick, red, dry skin.
While any part of your body can be affected, psoriasis plaques most often occurs on the elbows, knees, scalp, back, face, palms, and feet.
Like other autoimmune diseases, psoriasis occurs when your immune system — which normally attacks infectious germs — begins to attack healthy cells instead.
Who Gets Psoriasis?
According to the American Academy of Dermatology, about 7.5 million people in the United States have psoriasis, with the disease affecting Caucasians more than any other race.
The disease occurs about equally among men and women.
People with psoriasis generally see their first symptoms between 15 and 30 years of age; however, developing the disease between 50 and 60 years of age is also common.
Psoriasis patches can range from a few spots of dandruff-like scaling to major eruptions that cover large areas.
For some, psoriasis can clear up for months or even years at a time. This is known as remission.
Others experience psoriasis flares (or flare ups) in cyclical patterns; for instance, the disease will improve in the summer and worsen in the winter.
Psoriasis flares can be triggered by:
Stress: Stress is a major trigger for some people with psoriasis, either causing psoriasis to flare up for the first time or to make it worse after you’ve been diagnosed.
According to the National Psoriasis Foundation, a study of people who used light therapy for psoriasis found that listening to relaxation tapes during the therapy may help clear a psoriasis flare faster.
Cold weather: A trip to the Caribbean might be a good idea during the winter months if you have psoriasis and live in a cold climate, because the sun’s ultraviolet light turns off the skin’s immune system, which is overactive in people with psoriasis.
Dry skin: Anything that injures the skin can cause a psoriasis flare, including excessively dry skin.
The solution: Keep your skin moisturized. If you’re allergic to the fragrances in moisturizers, use a product that’s fragrance-free to avoid a rash.
Vaccinations: As with dry skin, puncturing the skin during a vaccination may cause a psoriasis flare, but that’s no reason to skip a needed shot.
One thing to keep in mind: If you’re on a potent psoriasis medication that suppresses your immune system (such as a biologic treatment), you shouldn’t take a live vaccine. Your body may not be able to fight off a live virus because of the medication you’re taking.
In that case, ask your doctor for a vaccine that contains a deactivated virus.
Beta blockers and lithium: Beta blockers to treat high blood pressure or lithium for a mental disorder can make psoriasis worse.
If you have high blood pressure, your doctor may be able to switch your medication to another drug that won’t affect your psoriasis.
If you’re taking lithium, your dermatologist may consider having you try light treatment or a topical therapy for psoriasis.
Upper-respiratory infections: Colds and other infections, especially strep throat, activate the immune system and can cause psoriasis to flare.
If you have psoriasis and develop a sore throat, get it treated and be sure to have a culture taken to check for strep. Long-term antibiotics may be an option for someone who has psoriasis and frequent sore throats.
Smoking: There’s some evidence that smoking can make psoriasis worse.
Diet: Studies haven’t shown any beneficial effects of taking nutritional supplements for psoriasis, but avoiding certain foods may reduce inflammation and help your psoriasis.
Additionally, studies have shown that many people with psoriasis may also have a gluten sensitivity, and eating a gluten-free diet can help reduce psoriasis symptoms.
In general, if you find that a certain food makes your psoriasis worse, try to avoid it.
Alcohol: For some people with psoriasis, having more than one or two drinks a day has been shown to cause psoriasis flares but the association is not a strong one. Flares from alcohol use could also be linked to psychological stress.
Types of Psoriasis
There are five types of psoriasis, yet people most often have only one type of psoriasis at a time. Each type has its own set of symptoms.
Most types of psoriasis go through cycles, flaring for a few weeks or months, then subsiding for a time or even going into complete remission.
Plaque psoriasis (also called psoriasis vulgaris) is the most common form. It appears as raised, red patches covered with a silvery white buildup of dead skin cells or scale.
The itchy, painful patches can crack and bleed, and commonly affect the scalp, knees, elbows, and lower back.
Guttate psoriasis often begins in childhood or young adulthood and is the second most common type of psoriasis.
Nearly 10 percent of people who get psoriasis develop guttate psoriasis, reports the National Psoriasis Foundation (NPF).
Inverse psoriasis, also known as intertriginous psoriasis, causes red lesions in folds of the body that may look smooth and shiny.
These lesions can occur on the genitals or areas near the genitals like the upper thighs and groin.
It's common for people with inverse psoriasis to have another type of psoriasis somewhere else on their body at the same time.
Pustular psoriasis causes white blisters of pus that surround red skin. The pus consists of white blood cells.
When pus-filled bumps cover the body, you may have bright-red skin and feel ill, exhausted, have a fever, chills, severe itching, rapid pulse, loss of appetite, or muscle weakness.
Erythrodermic psoriasis is a dangerous and rare form of the disease characterized by a widespread, fiery redness and exfoliation of the skin that causes severe itching and pain.
This type of psoriasis occurs once or more in 3 percent of people with psoriasis, according to the NPF.
Psoriasis; National Psoriasis Foundation.
Psoriasis: Who gets and causes; American Academy of Dermatology.
Psoriasis; Mayo Clinic.
Psoriasis; National Institutes of Health.