Like other autoinflammatory diseases, psoriasis occurs when your immune system — which normally attacks infectious germs — begins to attack healthy cells instead.
Signs and Symptoms of Psoriasis
Psoriasis plaques can range from a few spots of?dandruff-like scaling to major eruptions that cover large areas. The disease’s symptoms and appearance vary according to the type and severity of psoriasis.
Some common signs and symptoms include:
- Red patches or raised plaques of skin that are covered with silvery scales
- Dry or cracked skin that bleeds
- Burning, itching, or soreness near the affected areas
- Pitted or thickened fingernails or toenails
- Swollen joints (1)
Causes and Risk Factors of Psoriasis
Psoriasis, in general, is a genetic condition passed down through families. "It's likely that multiple genes need to be affected to allow psoriasis to occur and that it's frequently triggered by an external event, such as an infection,"?says?James W. Swan, MD, professor of dermatology at the Loyola University?Stritch?School of Medicine in?Maywood, Illinois.
Certain risk factors, such as a family history or being obese, may increase your odds of developing psoriasis.
According to the?National Psoriasis Foundation (NPF), at least 10 percent of people inherit genes that could lead to psoriasis, but only 3 percent or less actually develop the disease. (2) For this reason, it is believed that the disease is caused by a combination of genetics and external factors or triggers.
Psoriasis flares may be provoked by:
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. (3)
"Psoriasis is very stress-dependent. It flares very easily when patients are under stress, and it tends to improve when they're relaxed," says?Vesna?Petronic-Rosic, MD, a dermatologist and associate professor of medicine at the University of Chicago Medicine in Illinois. Stress management techniques, such as exercise, yoga, and meditation, may help manage psoriasis symptoms.
A trip to the Caribbean might be a good idea during the winter months if you have psoriasis and live in a cold climate. That’s?because the sun’s ultraviolet light turns off the skin’s immune system, which is overactive in people with psoriasis. Check with your dermatologist before traveling for sun safety skin tips and limit your daily exposure to no more than 10 minutes of direct sunlight.
Anything that injures the skin can cause a psoriasis flare, including excessively dry skin.
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. (4)
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.
If you have high blood pressure, your doctor may be able to switch your medication to another drug that won’t affect the 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. (7) 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.
There’s some evidence that smoking can make psoriasis worse.?According to a?study?published in March 2012 in the?American Journal of Epidemiology,?smokers have almost double the risk of developing psoriasis compared with people who’ve never smoked. (8) In a smaller?study?published in February 2016 in the?International Journal of Dermatology?that looked at twins, heavy smokers were more than twice as likely to have psoriasis. (9)
Studies haven’t shown any beneficial effects of taking nutritional supplements for psoriasis, but avoiding certain foods may reduce inflammation and help with 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. (10) In general, if you find that a certain food makes the psoriasis worse, try to avoid it.
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
Also called psoriasis?vulgaris,?plaque psoriasis?is the most common form of the disease. It appears as raised, red plaques covered with a silvery white?buildup?of dead skin cells, or scales. The itchy, sometimes painful plaques can crack and bleed, and commonly affect the scalp, knees, elbows, back, hands, and feet.
Often beginning in childhood or young adulthood,?guttate?psoriasis?is the second most common type of psoriasis. Nearly 10 percent of people who get psoriasis develop?guttate?psoriasis, according to the NPF. Guttate psoriasis is the type of psoriasis most closely linked to a recent strep infection. If you develop guttate psoriasis, you will also likely be tested for strep bacteria.
Also known as?intertriginous?psoriasis,?inverse psoriasis?causes red lesions in skin folds of the body that may look smooth and shiny. These lesions can occur on the genitals or in 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.
This causes white blisters of pus that surround red skin, often on the hands or feet. The pus consists of white blood cells. When pus-filled bumps cover the body, you may have bright-red skin and feel ill or exhausted, and have a fever, chills, severe itching, rapid pulse, loss of appetite, or muscle weakness.
This 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.?Erythrodermic psoriasis?occurs once or more in 3 percent of people with psoriasis, according to the NPF.
How Is Psoriasis Diagnosed?
There aren’t any special tests to help doctors diagnose psoriasis. Typically, a dermatologist will examine your skin and ask about your family history.
You’ll likely be given a diagnosis based on this physical exam.
In some situations, doctors will remove a small sample of the skin and examine it under a microscope. This might allow them to get a better look at the affected area and make a more accurate diagnosis. (11)
Duration of Psoriasis
Psoriasis is considered a chronic, lifelong condition. There currently isn’t a cure, but the disease can worsen or improve.
For some, psoriasis can clear up for months or even years at a time. This is known as remission.
Others experience psoriasis flares in cyclical patterns. For instance, the disease may get better in the summer and worsen in the winter. (12)
Treatment and Medication Options for Psoriasis
While psoriasis cannot be cured, there are effective options for treating it. Talk to your doctor about the benefits, risks, and side effects of any therapies you use.
Some medication to treat psoriasis includes:
- Topicals?Prescription and over-the-counter (OTC) treatments that are applied directly to the skin can minimize symptoms of psoriasis. These therapies contain different active ingredients and come as lotions, creams, shampoos, gels, sprays, or ointments.
- Biologics?Biologic drugs alter the immune system and are usually given as an injection. They include?Enbrel?(etanercept), Remicade?(infliximab), Humira?(adalimumab), Stelara?(ustekinumab), Simponi?(golimumab), Cosentyx?(secukinumab), Taltz?(ixekizumab), brodalumab, tildrakizumab, and Skyrizi?(risankizumab).
- Otezla?(apremilast)?This medicine comes as a pill and works by suppressing an enzyme that’s involved in inflammation.
- Oral Retinoids?These types of drugs are usually given if you have severe psoriasis that doesn’t respond to other treatments.
- Rheumatrex?(methotrexate)?This drug helps control inflammation.
- Cyclosporine (Gengraf, Neoral)?This medicine suppresses the immune system but can be taken for only short periods of time. (1)
Light therapy involves exposing your skin to controlled amounts of natural or artificial ultraviolet light to help reduce symptoms of psoriasis. You may receive this treatment alone or along with other medication. (1)
Prevention of Psoriasis
Some ways to reduce your risk of a psoriasis flare-up include:
- Take daily baths
- Keep skin moisturized
- Avoid triggers if you can
- Get a small amount of sunlight each day (1)
Complications of Psoriasis
Having psoriasis can increase your risk for developing a number of health conditions, including:
- High blood pressure
- High cholesterol
- Cardiovascular disease
- Liver disease
- Kidney disease
- Uveitis (an eye disease)
- Crohn’s disease
- Depression (14)
"Over the last few years, we've seen that maybe psoriasis plays a more integral part in metabolic syndrome, a collection of symptoms that can lead to diabetes and heart disease," says?Erin Boh, MD, chairman and a professor of dermatology at Tulane University in New Orleans and a member of the National Psoriasis Foundation board.
It is?estimated that up to 30 percent of people?with psoriasis will also develop?psoriatic arthritis, an autoimmune disease that affects the joints. According to the?National Psoriasis Foundation, psoriasis occurs before joint disease in 85 percent of psoriatic arthritis patients. (15)
The risks for psoriasis-related complications are greater the younger a patient is when diagnosed and the more severe the psoriasis. (16) Anyone with psoriasis should be aware that they are at risk for comorbid conditions and should monitor their overall health accordingly.
Research and Statistics: Who Has Psoriasis?
According to the?National Psoriasis Foundation, about 7.5 million people in the United States have psoriasis, with the disease affecting Caucasians more than any other race. (17)
The disease occurs about equally among men and women. According to the?National Institutes of Health (NIH), it is more common in adults, and you are at a greater risk if someone in your family has it. (18) A?study published in September 2016 in the journal?PLoS?One?concluded that “interactions between particular genes as well as genetic and environmental factors play an important role” in the disease’s development. (19)
People with psoriasis generally see their first symptoms between ages 15 and 30, although developing the disease between 50 and 60 years of age is also common. (20)
“The biggest factor for determining prognosis is the amount of disease someone has,” says?Michael P.?Heffernan, MD, a dermatologist at the San Luis Dermatology and Laser Clinic in San Luis?Obispo, California.
Many conditions are closely related to, and sometimes mistaken for, psoriasis.
Psoriasis and eczema may be tricky to tell apart.
If psoriasis affects your scalp, it might be hard to determine if it’s dandruff or psoriasis.
Other skin conditions like ringworm and pityriasis rosea are occasionally confused with psoriasis.
Is It Psoriasis or Eczema?
Like psoriasis, eczema is a very itchy skin condition. In fact, eczema usually results in a more intense itch than psoriasis. Scratching causes redness and inflammation of the skin, leading to a worsening of the eczema. Scratching can also cause a secondary bacterial infection.
Eczema is not a specific disease, but rather a term referring to a group of rash-like conditions. The most common type of eczema is caused by a reaction to irritants, like detergents, soaps, or household cleansers.
Eczema often shows up on the back of the knees or the inside of the elbows.
Eczema?can affect anyone and affects children more than psoriasis does. (21)
Is It Scalp Psoriasis or Dandruff?
"Most people with scalp psoriasis have it on other parts of their body as well," says?Dina D. Strachan, MD, a dermatologist and assistant clinical professor of dermatology at NYU Langone Medical Center in New York City.
Scalp psoriasis is sometimes confused with seborrheic dermatitis, or?dandruff. According to Dr. Strachan, dandruff — which causes a flaky, itchy scalp without signs of inflammation — tends to itch more than scalp psoriasis. “It has a greasy-appearing yellow scale,” Strachan says. “In contrast, psoriasis — whether it's on your scalp or any other body part — tends to have a thick, silvery scale."
Resources We Love
Favorite Organizations for Essential Psoriasis Information
The AAD represents the vast majority of practicing dermatologists in the United States. Its website includes a tool that allows you to search its database to find dermatologists in your area.
This global organization of physicians, health professionals, and scientists has provided a comprehensive website that offers a wealth of patient and caregiver resources, including educational videos, information on available medication and therapies, and a search tool to find a local rheumatologist.
Dedicated to supporting research to treat diseases affecting muscles, bones, joints, and skin, NIAMS offers a website that provides an exhaustive guide to skin conditions and related topics, as well as news on the most recent clinical trials.
As the leading patient advocacy group for people living with psoriatic disease, the NPF provides an enormous online support community for people dealing with psoriasis. It provides a wealth of patient resources, including personalized guidance on how to deal with the disease.
Founded in 2007, this alliance of two former psoriasis-based foundations operates a website offering information, advice, and support for those living with psoriasis, including a special section for children coping with the disease.
This patient advocacy group specializes in raising awareness about the seriousness of psoriasis and the need for additional medical research. It also provides resources and information to encourage patients to advocate for themselves when seeking medical care.
Favorite Sites for Financial Assistance and Advocacy
NPF Advocacy helps organize volunteers to share information and advocate with legislators for change in public policy regarding psoriasis.
This online nonprofit information resource helps users to find programs that help patients who can’t afford medication and healthcare costs.
The free PPA website helps users locate public and private assistance programs that can help cover expensive prescription medication costs.
Everyday Health contributor Howard Chang provides a firsthand perspective on psoriasis with an extra dose of encouragement, education, and empathy. Chang’s posts deal with the everyday details of living with psoriasis, including topics such as navigating the condition as a parent and how best to use the frequent time you spend in doctors’ waiting rooms.
Having been diagnosed with psoriasis at 15, blogger Joni Kazantzis writes about not only her personal battles with the condition but also the mental and physical challenges that each person with psoriasis must battle daily.
Todd Bello was diagnosed with psoriasis at age 28. Through his blog, Bello shares regular posts about living with psoriasis as well as his patient advocacy efforts as a very active volunteer for the NPF. His passionate efforts on behalf of others with psoriasis have helped build a community of support for those dealing with the condition.
With the motto “the P is silent but we are not!” this?blog is a frequently updated resource that covers a wide spectrum of psoriasis-related topics, including health, advocacy, and inspirational personal stories.
Soap Lake in Washington state has long been a popular destination for those dealing with skin conditions, thanks to the lake’s high natural mineral count and alkaline levels. In addition to specialized treatments, the Soap Lake Natural Resort and Spa also provides healthy dining options and a number of outdoor activities. Its accommodations also include in-room Jacuzzis that use water pumped from the lake, allowing you to experience the lake’s waters from the privacy of your room at any time during the year.
Set in a volcanic Icelandic landscape, the Blue Lagoon resort provides luxury accommodations and fine dining, complete with a private lagoon at the Silica Hotel. Its best feature, however, may be the clinic, which is widely popular in treating psoriasis. Guests can bathe in the mineral-rich seawater of the lagoon, while other treatments include UV light therapy and a host of internally developed skin-care products.
Created by the LEO Innovation Lab, this user-friendly app is a social media platform for people living with psoriasis. In addition to providing an easier way to connect with others dealing with the condition, it provides groups based on topic (parenting, diet, exercise, travel) and offers tools to help host meetups.
This app allows you to document and track how your psoriasis develops over time by using your phone’s camera. The split-screen feature enables you to compare your condition over time and relate it to the effectiveness of your treatment with your dermatologist.
Editorial Sources and Fact-Checking
- Psoriasis. Mayo Clinic. 2019.
- Genes and Psoriasis.?National Psoriasis Foundation.
- Basavaraj KH, Navya MA, Rashmi R. Stress and Quality of Life in Psoriasis: An Update.?International Journal of Dermatology. July 2011.
- Gunes A, Fetil E, Akarsu S, et al. Possible Triggering Effect of Influenza Vaccination on Psoriasis.?Journal of Immunology Research.?March 23, 2015.
- Kim G, Del Rosso J. Drug-Provoked Psoriasis: Is It Drug Induced or Drug Aggravated??Journal of Clinical and Aesthetic Dermatology. January 2010.
- Mohammad J. Lithium and Psoriasis: What Primary Care and Family Physicians Should Know.?Primary Care Companion to the Journal of Clinical Psychiatry. April 14, 2008.
- Sigurdardottir S, Thorleifsdottir R, Valdimarsson H, Johnston A. The Association of Sore Throat and Psoriasis Might Be Explained by Histologically Distinctive Tonsils and Increased Expression of Skin-Homing Molecules by Tonsil T Cells.?Clinical and Experimental Immunology. October 2013.
- Li W, Han J, Choi HK, Qureshi AA. Smoking and Risk of Incident Psoriasis Among Women and Men in the United States: A Combined Analysis.?American Journal of Epidemiology.?March 1, 2012.
- L?nnberg AS, Skov L, Skytthe A, et al. Smoking and Risk for Psoriasis: A Population-Based Twin Study.?International Journal of Dermatology. February 2016.
- Bhatia B, Millsop, J, Debbaneh M, et al. Diet and Psoriasis: Celiac Disease and Role of a Gluten-Free Diet.?Journal of the American Academy of Dermatology. August 2014.
- About Psoriasis. National Psoriasis Foundation. August 2019.
- Feldman, SR. Patient education: Psoriasis (Beyond the Basics). UpToDate. September 2019.
- Prevention. Stanford Health Care.
- Comorbidities Associated With Psoriatic Disease. National Psoriasis Foundation.
- About Psoriatic Arthritis.?National Psoriasis Foundation.
- Bronckers IM, Paller AS, van Geel MJ, et al. Psoriasis in Children and Adolescents: Diagnosis, Management, and Comorbidities.?Pediatric Drugs.?June 14, 2015.
- About Psoriasis and Psoriatic Arthritis in Children. National Psoriasis Foundation.
- Psoriasis.?National Institute of Arthritis and Musculoskeletal and Skin Diseases. March 30, 2017.
- Stawczyk-Macieja M, Rebala K, Szczerkowska-Dobosz A, et al. Evaluation of Psoriasis Genetic Risk Based on Five Susceptibility Markers in a Population from Northern Poland.?PLoS One. September 22, 2016.
- Psoriasis.?Cleveland Clinic. May 2016.
- Eczema vs. Psoriasis: Similarities, Differences, and Treatments. Penn Medicine. August 5, 2019.
- Scalp Psoriasis. National Psoriasis Foundation.