Psoriasis is a chronic skin condition that can cause red, scaly, and itchy patches (known as plaques) on various parts of the body, including the elbows, knees, scalp, feet, lower back, and genitals. Psoriasis is caused by an overreactive immune system that generates new skin cells at rapid rates. When these skin cells are produced quickly, they begin to build up on the surface of the skin and lead to patchy, scaly skin.
There are many types of psoriasis, including:
- Plaque psoriasis: The most common type of psoriasis, characterized by red or purple raised patches of skin covered by silvery scales (plaques).
- Erythrodermic psoriasis: A type of severe psoriasis that can cause psoriasis plaques to form on large portions of your body.
- Guttate psoriasis: This form of psoriasis often presents as red, teardrop-shaped bumps that are typically smaller than 1cm in size.
- Inverse psoriasis: Inverse psoriasis usually occurs in areas where your skin rubs against itself, like the armpits and groin. It can cause smooth, shiny red legions in these skin folds.
- Nail psoriasis: Also known as psoriatic nail dystrophy, this type of psoriasis affects the nails and causes discoloration and pitting
- Pustular psoriasis: Pustular psoriasis is a rare form of psoriasis. It is marked by painful, pus-filled blisters that develop most commonly on the hands and feet.
Psoriasis symptoms usually begin to appear between the ages of 15 and 25. Symptoms of psoriasis can be triggered or worsened by a number of factors, including:
- Injury to the skin (cuts, scrapes, bug bites, or sunburn)
- Infections (such as strep throat, bronchitis, or skin infections)
- Chronic health conditions (such as Type 2 diabetes and heart disease)
- Stress
- Cold, dry weather
- Alcohol consumption
- Medications (such as lithium and beta-blockers)
- Food allergies
If you have psoriasis, you may be at greater risk of developing other health conditions. Inflammation from psoriasis can lead to a form of arthritis known as psoriatic arthritis, which can cause joint pain and stiffness. Talk to your doctor if you are experiencing an itchy, persistent, and scaly rash, as this is the most common symptom of psoriasis.