Psoriasis Symptoms

The symptoms of psoriasis vary depending on the type you have. Some common symptoms for plaque psoriasis -- the most common variety of the condition -- include:

Patches of red, inflamed skin, often covered with loose, silver-colored scales. These patches may be itchy and painful and sometimes crack and bleed. In severe cases, the patches of irritated skin will grow and merge into one another, covering large areas.

Disorders of the fingernails and toenails, including discoloration and pitting of the nails. The nails may also begin to crumble or detach from the nail bed.

Patches of scales or crust on the scalp.

Small areas of bleeding where the skin is scratched.

Psoriasis can also cause psoriatic arthritis, which leads to pain and swelling in the joints. The National Psoriasis Foundation estimates that between 10% to 30% of people with psoriasis also have psoriatic arthritis.

What Triggers Psoriasis Flare-ups?

While the underlying cause of psoriasis stems from your body's immune system, certain triggers can make it worse or cause flare-ups. These include:

Cold and dry weather. Such weather can dry out your skin, which makes the chances of having a flare-up worse. In contrast, hot, sunny weather appears to help control the symptoms of psoriasis in most people.

Stress. Having psoriasis can cause stress itself and patients often report that outbreaks of symptoms come during particularly stressful times.

Some medications. Certain drugs, such as lithium (a common treatment for bipolar disorder), drugs for malaria, and some beta-blockers (used to treat high blood pressure, heart disease and some heart arrhythmias), can cause flare-ups of psoriasis. Some common painkillers -- called nonsteroidal anti-inflammatory drugs (NSAIDs) -- may also aggravate psoriasis, although they are still used in some people with psoriatic arthritis.

Infections or disease. Certain infections, such as strep throat or tonsillitis, can result in guttate or other types of psoriasis. Psoriasis may worsen in people who have HIV.

Trauma to the skin. In some people with psoriasis, trauma to the skin -- including cuts, bruises, burns, bumps, vaccinations, tattoos and other skin conditions -- can cause a flare-up of psoriasis symptoms either at the site of the injury or elsewhere. This condition is called "Koebner's phenomenon."

Alcohol. Using alcohol may increase the chances of flare-ups, at least in men.

Smoking. Some experts think that smoking can worsen psoriasis.