The classic symptoms of psoriasis are raised, red patches of skin topped with loose, silvery scales, usually on the knees or elbows.

There are several types of psoriasis. Symptoms for each type may vary in severity and appear in a wide array of combinations. In general, the major symptoms of psoriasis include:

• Bright red areas of raised patches (plaques) on the skin, often covered with loose, silvery scales. Plaques can occur anywhere, but commonly they occur on the knees, elbows, scalp, hands, feet, or lower back. Nearly 90% of people with psoriasis have plaque-type psoriasis.¹
• Tiny areas of bleeding when skin scales are picked or scraped off (Auspitz's sign).
• Mild scaling to thick, crusted plaques on the scalp.
• Itching, especially during sudden flare-ups or when the psoriasis patches are in body folds, such as under the breasts or buttocks.
• Nail disorders. Nail disorders are common, especially in severe psoriasis. Nail symptoms include:
  • Tiny pits in the nails (not found with fungal nail infections).
  • Yellowish discoloration of the toenails and sometimes the fingernails.
  • Separation of the end of the nail from the nail bed.
  • Less often, a buildup of skin debris under the nails.

Other symptoms of psoriasis may include:

• Similar plaques in the same area on both sides of the body (for example, both knees or both elbows).
• Flare-ups of many raindrop-shaped patches. Called guttate psoriasis, this condition often follows a strep infection and is the second most common type of psoriasis. It affects less than 10% of those with psoriasis.¹
• Joint swelling, tenderness, and pain (psoriatic arthritis).

Koebner's phenomenon can occur when a person with psoriasis has an injury (such as a cut, burn, or excess sun exposure) to an area of the skin that is not affected by psoriasis. Psoriasis patches then appear on the injured skin or any other part of the skin from several days to about 2 weeks after the injury. Because this response is common, it is important for people who have psoriasis to avoid irritating or injuring their skin.

Several other skin conditions have symptoms similar to psoriasis. Some medicine reactions can cause symptoms (such as reddened skin) similar to psoriasis. Talk to your doctor about the medicines you are taking.

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