Psoriasis is an autoimmune disease that causes areas of skin to become swollen and raised. It usually isn’t painful, but may make you feel uncomfortable. As the condition worsens, skin may develop an appearance of silvery scales.
Though psoriasis commonly appears on the scalp, elbows, knees and lower back, it can also occur in other locations. It may even lead to nail problems, including a condition called psoriatic arthritis.There are several types of psoriasis. The include:
- Plaque (discoid) psoriasis, which is the most common and looks like raised red patches with white scales
- Guttate psoriasis, which looks like red droplets on your skin and is often caused by a bacterial infection (streptococcus)
- Pustular psoriasis, which is uncommon and causes raised white bumps filled with pus