What Is Considered Moderate Plaque Psoriasis?

Psoriasis is classified as mild, moderate, or severe depending on the extent of skin involvement:

• Mild psoriasis: Affects less than 3% of the body and may present as isolated patches on the scalp and/or limbs.
• Moderate psoriasis: Affects about 3%-10% of the body, with lesions present on the limbs, torso, and scalp.
• Severe psoriasis: Affects more than 10% of the body, and large psoriatic lesions may be seen on the face, limbs, palms, soles, and skin folds.

In addition to red, scaly patches, other symptoms of psoriasis include:

• Itching
• Cracked, dry skin
• Scaly scalp
• Nails that are pitted, cracked, or crumbly
• Joint pain

The exact cause of psoriasis is unknown, but experts believe that it is triggered by an exaggerated immune system response that causes inflammation and rapid new skin cell growth.

Plaque psoriasis is an autoimmune disease, which means that part of your immune system becomes overactive and attacks normal tissues in your body. This causes skin cells to multiply about 10 times faster than normal, which leads to bumpy, red skin patches covered with white or silvery scales. 

Psoriasis can be passed down through families and tends to be slightly more common in women than in men. It is a chronic condition. Treatments can help reduce psoriasis symptoms or make them go away temporarily (remission), but flare-ups will occur throughout life.

Plaque psoriasis flare-ups can be triggered by:

• Skin injuries (cuts, scrapes, sunburn or surgery)
• Streptococcal infections 
• Larger skin folds due to excess weight gain
• Excessive perspiration
• Emotional stress
• Cold, dry weather
• Certain prescription medications such as lithium and beta-blockers

To diagnose psoriasis, a dermatologist will examine your skin, nails, and scalp for signs of the condition and ask about symptoms such as itchy or dry skin, joint problems, and family history of psoriasis or other skin conditions.

In rare cases, a skin biopsy may be ordered to confirm a diagnosis.

Possible complications of psoriasis include the following:

• Psoriatic arthritis: Approximately 20%-30% of individuals with psoriasis have joint inflammation with symptoms of arthritis. 
• Nail psoriasis: Approximately 50% of people with psoriasis have nail changes including pitting of nails, discolored, tender and painful nails and separation of the nail from the bed.

Psoriasis is a chronic skin condition that has no cure. Many people experience periods of remission (clear skin for months or years at a time) as well as occasional flare-ups where the condition worsens. Treatment can help relieve symptoms and prevent complications.

Treatment depends on the type and severity of the condition and may include:

• Medications
• Systemic therapies
• Phototherapy
• Psoralen plus ultraviolet A
• Laser therapy

Lifestyle changes that can help reduce symptoms include:

• Minimizing stress
• Eating healthy
• Avoiding smoking and alcohol
• Practicing good skincare