Is Psoriasis an Autoimmune Disease?

Medically Reviewed by Debra Jaliman, MD on September 14, 2023
4 min read

Psoriasis is more than skin deep. Those thick, scaly patches are only what you see on the surface. Deep inside your body, there’s a battle raging.

Experts believe psoriasis is an autoimmune disease. That means your body thinks its own tissues are foreign invaders that must be attacked. It also means that, unlike a simple rash, you can’t get rid of it with an over-the-counter skin treatment.

In fact, there’s no cure for psoriasis. The disease is chronic and relapsing, which means you’ll have it long-term but symptoms may come and go.

But there are medications, and they’re better than ever. Some people with psoriasis find lasting relief from drugs that target the immune system, in addition to a range of skin treatments.

Autoimmune diseases are complex, unlike a cold or the flu. It’s hard to pinpoint a single cause --and with psoriasis, there appear to be several possible causes:

Genes. Studies suggest that genes play a role. So, you may be more likely to get psoriasis if someone in your family has it. Researchers have found dozens of possible genetic links with psoriasis.

Environment. Genes alone probably aren’t enough to cause or worsen psoriasis. You also need a “trigger” -- something in the world around you that sets off psoriasis and psoriasis flares. These include:

  • Certain medications
  • Infections
  • Stress
  • Skin injury
  • Weather changes that dry out your skin

Your body’s immune system is supposed to protect you from diseases. When it’s working the way it should, immune cells identify and attack invaders like bacteria and viruses. But when you have an autoimmune disease, cells in your immune system go haywire.

With psoriasis, your T cells (a type of white blood cell) become highly active and attack skin cells by mistake. Then other parts of your immune system spring into action. Inflammation happens, and skin cells grow too fast.

What’s “too fast”? In healthy people, new skin cells normally travel from deep within the skin to the surface of the skin in about a month. The process is called cell turnover. With psoriasis, new skin cells rise to the surface within days. The rapid cell turnover leads to thick patches of skin.

Not only is psoriasis likely an autoimmune disease, it is also linked with other autoimmune diseases. The most common tie is with psoriatic arthritis (PsA).

Some research shows that around 30% of people, when diagnosed with psoriasis, already have PsA, a disease that affects joints and the areas where tissue attaches to bone. Other research suggests that even more people with psoriasis -- as many as 40% -- will get PsA, usually within 5 to 10 years of skin symptoms.

Signs of PsA include:

  • A swollen, sausage-like finger or toe (dactylitis)
  • Nail changes or problems
  • Pain and swelling in one or more joints
  • Pain in the low back/buttocks area (sacroiliac joints)

Other autoimmune conditions linked with psoriasis include:

If you think you have psoriasis, see your doctor right away. It shouldn’t take long to get an answer once you’re there. Usually, all it takes to diagnose psoriasis is a discussion about your medical history and an exam of your skin, scalp, and nails. Some doctors may also take a small sample of skin to examine under a microscope. This test is called a biopsy.

While you’re at the doctor, be sure to speak up if you have any other symptoms besides skin and/or nail problems -- especially if you have joint issues, including:

  • Heel pain
  • Morning stiffness that improves during the day
  • Swelling just above your heel
  • Swollen or tender joints

Because psoriasis often goes along with PsA, you’ll want to know as soon as possible if you have both. Early diagnosis and treatment of PsA can help prevent permanent damage to your joints.

Managing any disease can be a challenge. When you have psoriasis, you may need to keep track of multiple medications, such as: prescription skin creams, ultraviolet light therapy, and powerful medicines. That’s in addition to things you might do at home to look and feel better, from daily oatmeal baths to avoiding alcohol.

Managing other diseases in addition to psoriasis only adds to your burden. You could be facing:

It’s a lot to handle, but your doctor can help in ways you might not have thought about. The key is to be an active partner in controlling your diseases, not just a passive listener. You can start by bringing your doctor a list of your concerns -- emotional, financial, and medical. Here are some examples to get you started:

  • Why are you prescribing a certain medication? Does it have risks that I should know about, especially considering other drugs I take?
  • I don’t take certain medications regularly because of the cost. Do I have other options?
  • I have a health goal to take fewer medications / lose 15 pounds / feel less depressed, but I need help. Can you help me create a plan?

If you don’t like what you hear, or don’t feel you’re getting the help you need, remember it never hurts to get a second opinion.