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What causes psoriasis?

The exact cause isn’t known, but genetics and environment contribute to the development of psoriasis

genetics play a role

Your parents never had psoriasis, so why do you? Scientists estimate that at least 10% of people inherit one or more genes that can cause psoriasis; however, only 2% or 3% of this population actually develop the disease. The reason? You need the right mix of genes and exposure to triggers to get it. So, while your parents may have passed the susceptibility genes to you, they didn’t have the “right” gene mix to get it themselves.

Environmental factors may cause a flare-up

While psoriasis is a chronic disease, certain triggers around you can cause it to start or worsen, known as a flare-up. Triggers are not the same for everyone, so take a look at this list to see what may affect you:

  • Infections, such as strep throat or skin infections
  • Injury to the skin, such as a cut, a scrape, bug bites, or a severe sunburn
  • Stress
  • Cold weather
  • Smoking
  • Heavy alcohol consumption
  • Certain medications, including: lithium; high blood pressure medications such as beta blockers; antimalarial drugs; and iodides

Once you know what triggers your flare-ups, you can try to find ways to avoid them. If you need help with triggers such as smoking, alcohol, and medications, talk to your doctor to see if he or she can help.

Not sure of your triggers?

Take this informative quiz to learn what could be causing your flare-ups, and learn more about possible triggers!

SHOW TRIGGERS & TRAITS