The basics

Psoriasis is an autoimmune disorder characterized by inflamed areas of skin. People with the most common type of psoriasis, plaque psoriasis, develop thick patches of red and white scaly skin known as lesions. These lesions may appear anywhere on the body but they typically show up on the elbows, knees, and scalp.

Approximately 7.5 million people in the United States are affected by psoriasis.

You may be wondering whether psoriasis is contagious. Is it possible to transmit the skin condition to someone else if they touch one of these lesions? We answer your questions, including what causes psoriasis and how to reduce your risk of flare-ups.

Is psoriasis contagious?

Psoriasis is never contagious. Unlike some other skin conditions such as scabies, impetigo, and MRSA, psoriasis isn’t caused by contagious bacteria or another type of infection.

Psoriasis is an autoimmune disorder. According to the American Academy of Dermatology (AAD), you must have specific genes to develop the disease. Having the gene doesn’t necessarily mean you will develop the condition. If you do have these genes, however, environmental triggers generally activate this condition.

Five different types of psoriasis exist. Each type has a unique rash which may resemble contagious skin conditions:

  • Plaque psoriasis causes red, raised patches of skin. These patches are typically covered by a silvery buildup of scaling or dead skin cells.
  • Guttate psoriasis causes small red spots all over the skin. It often happens after an illness or infection, such as strep throat.
  • Pustular psoriasis causes painful, raised, pus-filled bumps on the palms and soles that may itch. Pustular psoriasis may also cause flu-like symptoms, such as fever, chills, and loss of appetite.
  • Inverse psoriasis causes sore, red patches of skin. It usually occurs in the skin folds.
  • Erythrodermic psoriasis causes the skin to become bright red. It resembles a severe, all-over sunburn. The body can’t maintain its temperature and may cause rapid heart rate, intense pain, and intense itching. Erythrodermic psoriasis is an emergency condition.

How do you develop psoriasis?

The exact cause of psoriasis isn’t fully understood. It’s thought that overactive T cells, which are cells that fight off viruses and bacteria in your body, are involved. In people with psoriasis, T cells attack healthy skin cells and activate other immune responses. This increases the production of healthy skin cells, T cells, and other white blood cells.

As a result, too many skin cells accumulate on the skin’s outer layer. This is why some types of psoriasis cause the skin to have a scaly appearance. It normally takes weeks for new skin cells to form, but in people with psoriasis, skin cells form within days. The body doesn’t shed the excess cells and psoriasis lesions occur.

People with a compromised immune system, including those with HIV or those who get repeated infections, have a higher risk of getting psoriasis.

What triggers a psoriasis flare?

Many environmental and lifestyle factors may trigger psoriasis flares. Not everyone with psoriasis has the same triggers. Common triggers are:

  • sun exposure
  • smoking
  • infections
  • skin trauma, such as cuts, bug bites, and burns
  • stress
  • exposure to cold temperatures
  • certain medications, such as lithium, blood pressure medications, and iodides
  • heavy alcohol use

Smoking isn’t just a psoriasis trigger. It may also be involved in its development and increase the severity of the disease.

Research shows that smoking may cause one in five cases of psoriasis and doubles your risk of getting the condition. This may be due to the effects of nicotine on skin cells, skin inflammation, and your immune system.

Although some say that allergies and certain foods can trigger psoriasis flares, these claims are mostly anecdotal.

When is psoriasis typically diagnosed?

According to the National Psoriasis Foundation, psoriasis often develops between the ages of 10 and 35. It may appear at any age, though. Up to 15 percent of people with psoriasis are diagnosed before age 10. In rare cases, infants can develop the condition.

Dermatologists usually diagnose psoriasis, although many primary care physicians will recognize it. Most doctors diagnose psoriasis by performing a visual skin exam and assessing family medical history. You’re considered at risk of developing psoriasis if you have one parent with the disease. If you have two parents with psoriasis, this risk is higher.

In some cases, a doctor can perform a skin biopsy to confirm the diagnosis and the type of psoriasis you have.

No cure for psoriasis is available yet. The disease may go into remission, however. The goal of psoriasis treatment is to stop or slow the appearance of any lesions, and then discover any triggers to mitigate outbreaks. This is done through slowing the growth of skin cells, reducing inflammation and scaling, and smoothing the skin. You may be able to accomplish this through medication, topical treatments, and light therapy.

The bottom line

Psoriasis isn’t contagious in any form. It’s an autoimmune condition — not an infectious disease. If you hear someone question that fact, take a moment to educate them. Doing so can help promote an environment of acceptance and understanding.

The results of a 2003 survey conducted by a program called “Beyond Psoriasis: The Person Behind the Patient,” reinforces why psoriasis education is so important. Low self-confidence was reported in 73 percent of people with severe psoriasis and 48 percent of people with moderate psoriasis.

Not only that, but 64 percent of respondents said the public is afraid psoriasis is contagious and 45 percent said people with psoriasis are ridiculed. With this in mind, it’s just that much more important to educate yourself and others about the causes and symptoms of the condition.