Rupioid psoriasis is a type of psoriasis that causes thick plaques that may resemble barnacles or oyster shells. It’s rare, but it may cause severe symptoms for some people.

Psoriasis is an autoimmune disease that causes rashes that are often itchy and scaly. The most common type, plaque psoriasis, is characterized by raised and red patches of skin. Rupioid psoriasis is a type of plaque psoriasis.

Some people with rupioid psoriasis develop severely itchy or painful plaques that can cover large areas of the body, such as the back or limbs. Due to the thickness of the plaques, it can be challenging to treat with creams, but many people have relief with medications taken in other ways, such as injections.

Learn more about rupioid psoriasis, such as potential causes, symptoms, and treatment options.

Rupioid psoriasis is a rare type of plaque psoriasis. It’s frequently associated with immunosuppressive conditions like HIV. Doctors don’t know the exact cause of plaque psoriasis, but it’s thought to develop when your immune system starts attacking healthy skin cells. This autoimmune reaction can cause inflammation and the formation of plaques.

Rupioid psoriasis seems to occur more frequently in males than females and is particularly rare among children.

Psoriasis is thought to develop due to a combination of factors, including genetics and environmental factors. People with direct family history of psoriasis seem to be more likely to develop it, too.

Plaque psoriasis often develops after a previous skin injury, such as:

  • cuts
  • scrapes
  • insect bites
  • sunburns

Symptoms often appear after exposure to a certain trigger. Along with skin injuries, common triggers include:

  • stress
  • infections
  • frequent or excessive alcohol consumption
  • weather changes like changes in humidity
  • smoking
  • alcohol
  • sunlight
  • some medications

Psoriasis and medications

Psoriasis flare-ups have been linked to many types of medications, such as:

  • beta-blockers
  • antimalarial drugs
  • bupropion
  • calcium channel blockers
  • captopril
  • fluoxetine
  • lithium
  • penicillin
  • terbinafine
  • interferons
  • interleukins
  • fluoxetine
  • glyburide
  • granulocyte colony-stimulating factor

Rupioud psoriasis and other forms of plaque psoriasis cause raised plaques of skin that usually have a silvery and crusted layer over them.

Unlike other forms of plaque psoriasis, the characteristic sign of rupioid psoriasis is thick and crusty plaques that resemble oyster shells or barnacles.

Plaques may also:

  • cause pinpoint bleeding when the area is scraped (Auspitz sign)
  • be a darker color than plaques caused by other types of psoriasis
  • have well-defined borders

Plaques can occur anywhere, but often occur on your:

  • torso
  • scalp
  • knees
  • elbows
  • arms
  • legs

Here are some examples of rupioid psoriasis. Note the barnacle or oyster shell-like appearance of the plaques.

People with rupioid psoriasis seem to be particularly prone to developing a complication called psoriatic arthritis. Psoriatic arthritis can cause symptoms like:

  • joint pain and tenderness
  • swollen joints
  • joint stiffness
  • reduced range of motion
  • warmth in your joints

People with psoriasis may also be at an increased risk of developing some other conditions, such as:

  • cardiovascular disease
  • eye inflammation (uveitis)
  • some other autoimmune conditions

It’s important to seek medical help if you develop potential symptoms of psoriasis, such as unexplained rashes or itchiness. It’s also important to visit your doctor if you’ve previously been diagnosed but you develop new or worsening symptoms.

Your doctor can recommend how to reduce your symptoms and tell you if you may benefit from treatments like prescription medications to reduce your symptoms.

The initial step to getting a psoriasis diagnosis usually involves visiting your primary healthcare professional. They will ask you questions about your symptoms, review your medical history, and examine your skin during your initial appointment.

They may highly suspect psoriasis based on the appearance of your plaques. To confirm the diagnosis, they may take a small sample of your skin called a biopsy so that it can be examined under a microscope.

They may refer you to a doctor who specializes in conditions of the skin and hair, called a dermatologist.

The best treatment for you depends on the severity of your symptoms. Your doctor may suggest trying medicated anti-inflammatory creams. However, rupioid psoriasis can be particularly hard to treat with topical options because the thick plaques may make it difficult for them to penetrate your skin.

Your doctor may prescribe oral medications or medications administered through injection in combination with topical medications to reduce immune system activity. These medications may include:

  • methotrexate
  • cyclosporine
  • ustekinumab
  • steroids

It’s not always possible to prevent psoriasis, but you may be able to reduce your number of flare-ups by avoiding your triggers. Many people find it helpful to carry a journal or keep a list on their phone tracking when their flare-ups occurred and which factors might have contributed.

Psoriasis doesn’t have a cure, but receiving proper treatment can help you keep your symptoms under control. Psoriasis often comes in flare-ups. Identifying your triggers and figuring out when your symptoms get worse is important for anybody living with psoriasis.

You may have to try several treatment options before you find one that’s effective for you. But many people are eventually able to keep their symptoms under control.

Rupioid psoriasis is a rare but often severe form of psoriasis that causes plaques that may resemble oyster shells or barnacles. These plaques can become very itchy or painful.

It’s important to speak with a doctor if you think you may have psoriasis or if you think your psoriasis is getting worse. They may recommend trying treatment options like prescription creams or medications administered through injections.