Psoriasis is a skin disease marked by scaly skin patches. But the cause of this condition is complicated, and doctors don’t know a lot about why things like stress and upper respiratory infections make psoriasis worse in some people, says Steven Feldman, MD, PhD, professor of dermatology, pathology, and public health sciences at the Wake Forest University School of Medicine in Winston-Salem, N.C.
Doctors agree, however, that psoriasis is related to your immune system. When something triggers an immune system response in a person with psoriasis, the body begins to make more skin cells than usual and those cells collect on the skin, resulting in the silvery scales characteristic of plaque psoriasis.
According to the National Psoriasis foundation, as many as 7.5 million Americans have psoriasis. Both men and women have the same risk of getting psoriasis and most people with the condition experience their first psoriasis flare between ages 15 and 25.
Determining Your Psoriasis Triggers
Although psoriasis triggers can vary from person to person, finding out what causes your skin to flare up is one of the best ways to try to control your condition. Here are some of the most common triggers:
- 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 like the northern United States or Canada. “Cold winter weather makes psoriasis worse, partly because sunshine makes it better,” Dr. Feldman says. Along with the cold temperatures, the drier air and the shorter days can trigger a psoriasis flare.
Taking a trip to a tropical vacation may help, as because the sun’s ultraviolet light turns off the skin’s immune system, which is overactive in people with psoriasis. In fact, using a light box or tanning bed is the primary treatment for people with bad psoriasis. However, Feldman doesn’t recommend using ultraviolet light as a treatment unless you’ve been advised to do so by a doctor. And when you’re in the sun, protect your hands and face with a hat and sunscreen if you don’t have psoriasis on either of those areas, he says. Conversely, a sunburn can trigger a flare.
- 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, be sure to 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. “If a patient has psoriasis at the injection site, we’d give them a little cortisone to clear it up,” Feldman says.
One thing to keep in mind, says Feldman: 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 the dead 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. “But whether it does or doesn’t, you should quit,” Feldman says. “What smoking does to your heart and your risk of cancer is so much more important than the psoriasis risk.”
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, a recent study has 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, Feldman suggests.
Because people with psoriasis have an increased risk for cardiovascular disease, it’s especially important to follow a healthy diet and to exercise. “It’s important for everybody,” he says, “and it’s even more important for people with psoriasis.” While the link between psoriasis and heart disease is not yet clear, psoriasis patients are more likely to have risk factors like hypertension and high cholesterol.
- 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 a result of psychological stress, according to Feldman.
Although psoriasis is pretty unpredictable, it’s good to know that you can take some control by avoiding these possible triggers.