12 Psoriasis Causes and Risk Factors

Psoriasis turns your skin cells into type A overachievers: They grow about five times faster than normal skin cells. And your body can't keep up. The old ones pile up instead of sloughing off, making thick, flaky, itchy patches.

Why do these cells go a little haywire? There's more going on under the surface of this skin disease.

Researchers think something sets off your immune system. The exact reason is a mystery. But it's likely a combination of genetics and triggers.

1. Your Genes and Your Immune System

Little bits of your DNA, called genes, are instructions for your cells. They control things like your eye and hair color, if you can taste certain things, and other ways your body works. Some genes are only active at certain times.

When you have psoriasis, the genes that control your immune system signals get mixed up. Instead of protecting your body from invaders as it's designed to do, it promotes inflammation and turns skin cells on overdrive.

Scientists have found about 25 genes that are different in people with psoriasis. They think it takes more than one to cause the disease, and they're looking for the main ones.

About 10 in every 100 people have genes that make them more likely to get psoriasis, but only two or three of them actually do.

2. Hormone Changes

The disease often shows up or flares during puberty. Menopause can also trigger it. During pregnancy, your symptoms may get better or even go away. But after the baby’s born, you might have a flare.

3. Alcohol

Heavy drinkers have a higher risk, especially younger men. Alcohol can make treatments less effective, too.

4. Smoking

Lighting up can double your risk of getting psoriasis. If you also have relatives with the disease, you're nine times more likely to get it. And smoking makes it harder to get rid of symptoms. It's closely linked with a hard-to-treat type called pustular psoriasis, which affects the palms of your hands and the soles of your feet.

5. Stress

Scientists think your immune system may respond to emotional and mental pressures the same way it does to physical problems like injuries and infections.


6. Medications

Some treatments can make psoriasis worse. These include:

7. HIV

Psoriasis usually is worse in the beginning stages of HIV infection, but then it gets better after you start certain treatments.

8. Other Infections

Strep infections, in particular, are linked with guttate psoriasis, which looks like small, red drops. Kids will often have strep throat before their first flare. Earaches, bronchitis, tonsillitis, or a respiratory infection such as a cold, the flu, or skin problems.

9. Sunlight

A little natural sunlight is good for most people with psoriasis. But for a few, the sun makes their condition worse. So can a bad sunburn, so protect your skin if you’re going to be outside.

10. Skin Injuries

A cut, scrape, bug bite, infection, or too much scratching can trigger the condition.

11. Weight

People who are obese tend to get plaques in their skin creases and folds.

12. Weather

Your psoriasis might be worse in the winter. Dry air, less natural sunlight, and cold temperatures can make symptoms worse. Keep your skin moist, and try a humidifier at home.

WebMD Medical Reference Reviewed by Debra Jaliman, MD on November 16, 2018



National Psoriasis Foundation: "Psoriasis Causes and Known Triggers," "Genes and Psoriasis," "Stress," "How Cigarettes and Alcohol Affect Psoriasis," "Pregnancy and Nursing," "Frequently Asked Questions: Psoriasis in spring, summer, fall and winter."

NHS Choices: "Psoriasis - Causes."

Medscape: "Dermatological Management of Human Immunodeficiency Virus (HIV)."

American Osteopathic College of Dermatology: "Palmoplantar Pustulosis."

Ceovic, R. BioMed Research International, 2013.

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