Annular psoriasis refers to psoriasis that forms in a ring-like pattern with well-defined borders and central clearing. Treatments may include topical ointments, oral medications, and more.

Annular psoriasis can occur in both plaque psoriasis and pustular psoriasis. A doctor will be able to determine the type of psoriasis and advise on which treatments may help.

Read on to find out more about annual psoriasis. This article discusses symptoms and causes, treatment options, diagnosis, and more.

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Annular psoriasis is a type of psoriasis where the lesions form a ring-like (annular) shape with central clearing. This means that it often presents with an area of skin in the middle of the ring with no obvious lesion.

The ring-like pattern can occur in both plaque and pustular psoriasis. Although these are distinct conditions, they can occur together or one following the other.

Plaque psoriasis is the most common form of psoriasis. It typically presents with well-defined, symmetrical lesions of inflamed skin that may be extremely itchy.

Learn more about plaque psoriasis.

Pustular psoriasis occurs in about 3% of people with psoriasis. It typically presents with white or yellow pus-filled, painful bumps on the skin. Inflamed skin often surrounds the bumps.

Learn more about pustular psoriasis.

Annular psoriasis causes lesions in a ring-like pattern. The center of the ring may be clear skin. This is known as central clearing.

The other symptoms of annular psoriasis will vary some based on the underlying type of psoriasis. However, both plaque and pustular psoriasis do share some common features.

Both involve inflamed skin that may appear red on lighter skin or purple on darker skin. They can also both cause pain or itchiness. A person with plaque psoriasis may develop pustular psoriasis at some point in their life.

Pustular psoriasis can be generalized, appearing over large areas of the body, or localized. Localized pustular psoriasis can affect areas such as:

  • palms of the hands
  • soles of the feet
  • tips of the toes and fingers

Plaque psoriasis can appear anywhere, but it often affects the:

  • scalp
  • knees
  • elbows
  • torso

It often affects both sides symmetrically and may involve the nails.

Learn more about the symptoms of psoriasis.

The exact underlying cause of psoriasis is not clear. Experts believe that it involves the immune system attacking healthy skin cells. This may be due to genetic mutations that may run in families.

Psoriasis is not contagious. A person cannot catch psoriasis from direct or indirect contact with a person who has it.

Both plaque and pustular psoriasis share similar triggers, which can cause a flare in symptoms. Some common triggers include:

  • damage to skin and sun exposure
  • certain medications
  • stress
  • illness or infection
  • tobacco use
  • excess alcohol consumption
  • pregnancy

Learn more about psoriasis triggers.

Treatment may start with topical ointments. A doctor may recommend over-the-counter or prescription-strength topicals that a person can apply directly to the affected area. This may help reduce symptoms such as inflammation and itchiness.

Other treatments a doctor may recommend include:

  • phototherapy, which uses light to provide treatment directly to annular psoriasis patches
  • injectable or IV biologics, which are systemic options that uses living organisms to target the immune system and reduce inflammation
  • oral medications, which target the immune system to help reduce inflammation

A person may need to try several different approaches under their doctor’s supervision to figure out what the best option is for them.

Discover home remedies for psoriasis.

Diagnosis of plaque psoriasis is typically clinical. This means that a doctor may be able to confirm the diagnosis based on the physical appearance of the condition alone.

A doctor does not typically need to order a skin biopsy on a lesion. However, in some situations, they may wish to do so to confirm the diagnosis. A skin biopsy involves removing a small sample of the affected skin for laboratory analysis.

The doctor may refer the person to a specialist such as a dermatologist. They can recommend and prescribe treatments to help alleviate symptoms.

Annular skin lesions appear as well-defined, ring-like patches on the skin with central clearing.

Nummular skin lesions appear as coin-shaped patches with poorly defined borders.

Both can cause discoloration of the skin as well as itchy or painful areas of skin.

A person should contact a doctor if they develop a rash or skin lesions. The doctor will be able to determine the type of lesion and advise on suitable treatment options.

Learn about nummular eczema.

Annular psoriasis may occur in both plaque and pustular psoriasis. “Annular” refers to a ring-like appearance with a clear center.

The symptoms and areas where a person may develop annular psoriasis may depend on the underlying type. Typically, causes and treatment will be similar, though what treatment works best can vary by person.

Treating psoriasis with medications and avoiding triggers are two ways a person can manage their condition. If a person develops lesions, a helpful first step can be contacting their doctor for a diagnosis.