Introduction

Psoriasis is a chronic skin condition. There are several types of psoriasis, the most common of which is plaque psoriasis, which causes cells to build up quickly on your skin’s surface. This leads to raised patches of skin that develop silver scales.

Psoriasis causes itchiness and irritation and may be painful. There’s no cure for psoriasis, but treatment can ease symptoms. Read on to get the scoop on the facts, prevalence, symptoms, and more.

Prevalence

Anyone can get psoriasis, regardless of age. But psoriasis is most likely to appear first between the ages of 15 and 35 years old. Males and females get it at about the same rate.

According to the International Federation of Psoriasis Associations (IFPA), about 3 percent of the world’s population has some form of psoriasis. In the United States, there are about 150,000 new cases every year. It affects about 7.5 million U.S. people, according to the American Academy of Dermatology (AAD).

Symptoms

Psoriasis causes patches of red, rough skin. In mild cases, it may cause patches of dry, itchy skin on your scalp. In severe cases, it can spread over large areas of your body and cause a variety of uncomfortable symptoms.

With psoriasis, your red, rough skin takes on the appearance of silver scales. Your skin may also be dry and cracked, which can make it bleed. Your fingernails and toenails can become thick and pitted. You may have occasional flare-ups followed by times when you don’t have symptoms.

Types of psoriasis

Plaque psoriasis

This is the most common type of psoriasis. It makes up about 80 percent of cases. It causes red skin lesions and silver scales that can occur anywhere on the body. These can even appear on the inside of your mouth or on your genitals. Plaque psoriasis can be itchy and painful.

Scalp psoriasis

Psoriasis can also occur on your scalp. The main symptom is a dry, itchy scalp. It’s estimated that about half of people with psoriasis will have a flare-up on the scalp. You may also notice flakes in your hair and on your shoulders. Scratching from these symptoms can cause bleeding.

Nail psoriasis

Psoriasis of the fingernails and toenails can cause your nails to appear pitted and discolored. Your nails can get weak and crumble. They may even separate from your nail bed. When this happens, it’s called onycholysis.

Psoriatic arthritis

According to the Centers for Disease Control and Prevention (CDC), about 10 to 20 percent of people with psoriasis go on to develop psoriatic arthritis. As with other types of arthritis, symptoms include joint stiffness and swelling. There are five subtypes of psoriatic arthritis and many treatment options to try.

Guttate psoriasis

This type of psoriasis can be triggered by an infection. It generally affects children and young adults and is estimated to affect about 10 percent of people with psoriasis. Skin sores appear on the scalp, torso, arms, and legs. The scales are finer than those from other types of psoriasis. Some people with this type have only one outbreak that clears up without treatment, while others continue to have outbreaks over time.

Inverse psoriasis

Inverse psoriasis may cause patches of red, irritated skin in your armpits, under your breasts, or around your genitals and groin. This is because this type of psoriasis affects your skin folds. It may be triggered by a fungal infection and perspiration can make symptoms worse.

Pustular psoriasis

Pustular psoriasis is a rare type of psoriasis that can come on quickly. First, your skin becomes red and tender to the touch. Within hours, pus-filled blisters appear. Blisters may clear up and come back from time to time. Flare-ups may be triggered by infection, irritation, or even by some medications. In addition to itching, pustular psoriasis can cause:

  • fever
  • chills
  • diarrhea
  • kidney and liver problems

These issues can be severe. One type of pustular psoriasis demands immediate medical care. You may need to be hospitalized to treat it.

Erythrodermic psoriasis

This rare but severe type of psoriasis can affect your whole body. It’s estimated to affect less than 3 percent of people with psoriasis. Symptoms include:

  • red, peeling skin
  • itchiness
  • burning sensation

Medications, such as corticosteroids, may trigger erythrodermic psoriasis. Other triggers include phototherapy treatment, sunburn, and psoriasis that has spread out of control. This form of psoriasis can be life-threatening and if you have this type of flare, you should see a doctor immediately.

Cause and risk factors

Causes

The exact cause of psoriasis isn’t known. It’s an autoimmune condition, which means it involves a problem with your immune system response. In your immune system, it’s the job of your T cells to attack foreign organisms to keep you healthy. In psoriasis, the T cells mistakenly attack healthy skin cells. This leads to an overproduction of new skin cells, T cells, and white blood cells. This allows dead skin cells to accumulate. The accumulation creates the hallmark scaly patches seen in psoriasis.

No type of psoriasis is contagious. You can’t catch psoriasis from someone who has it.

Risk factors

According to the National Psoriasis Foundation, genetics may play a role in the development of the condition. You’re 10 percent more likely to get psoriasis if one of your parents has it. Your risk is even higher — 50 percent higher — if both of your parents have it.

Bacterial or viral infections may also be a factor. According to the Mayo Clinic, you’re at greater risk of getting psoriasis if you have HIV. Children with frequent bouts of strep throat or other recurring infections also have a higher risk. This may be due to the way these infections affect your immune system.

Certain medications may also play a role. The following have all been linked to psoriasis:

  • lithium
  • beta-blockers
  • tetracycline
  • nonsteroidal anti-inflammatory drugs (NSAIDs)
  • malaria drugs

Smokers have a higher risk of psoriasis. If you already have the condition, smoking may make it worse.

Obesity has also been associated with psoriasis, but the question remains: Which came first? Does psoriasis cause obesity or does obesity increase the risk of psoriasis? There’s some evidence that obesity predisposes individuals to the development of psoriasis. So it’s important to eat healthy and maintain a healthy weight to also avoid psoriasis-related health problems such as:

Finally, flare-ups may be brought on by stress or triggered by certain drugs. These include beta-blockers, interferon, and lithium.

Tests and diagnosis

In the United States, primary care doctors are the first line of care in 58 percent of new cases. According to the Cleveland Clinic, psoriasis causes 3 million office and hospital visits per year. Dermatologists manage 80 percent of these cases. These are doctors who specialize in treating skin conditions.

In many cases, a doctor can diagnose psoriasis by conducting a physical exam and reviewing your medical history. If there’s any doubt, your doctor may do a biopsy to confirm the diagnosis. Psoriatic arthritis will need additional testing.

Treatment

There’s no cure for psoriasis, but treatment can slow down the growth of skin cells and relieve pain and itching.

For mild cases, there are a variety of over-the-counter (OTC) topical ointments that can help. There are also a number of things you can do at home that may help. Prescription corticosteroids can also help, but they’re often only used during flare-ups. Other topical treatments include:

  • calcipotriene (Dovonex) and calcitriol (Rocaltrol): These drugs are synthetic (man-made) vitamin D. They work by slowing the growth of skin cells.
  • anthralin (Dritho-Scalp): This medication regulates DNA activity in skin cells and remove scales.
  • tazarotene (Tazorac): This is a derivative of vitamin A. It’s used to normalize DNA activity and decrease inflammation.
  • tacrolimus (Prograf) and pimecrolimus (Elidel): These drugs work by reducing inflammation.
  • salicylic acid: This is used to get rid of dead skin cells.
  • coal tar: This medication works by reducing inflammation and scaling.
  • moisturizers: These are used to soothe dry skin.

Light therapy and natural sunlight can also ease psoriasis symptoms. This is because light can slow skin cell growth and scaling.

Other treatment options are oral and injectable drugs. These include retinoids, methotrexate, and cyclosporine. Severe psoriasis may also be treated with biologics. Biologic drugs alter your immune system.

Complications

Having psoriasis increases your risk of psoriatic arthritis. It may also increase your risk of:

Psoriasis can also impact your quality of life. Frequent bouts of psoriasis can cause people to withdraw from social situations or work. This may lead to feelings of depression.

Talk with your doctor

If you have psoriasis, see your doctor as often as they suggest. They can help you find a treatment plan that works for you. Because of the risk of complications, your doctor will do regular exams and screenings to check for related conditions.