6 Common Triggers of Psoriasis Flare-Ups

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Psoriasis is a complicated, chronic skin disorder. Scientists are still struggling to understand what exactly occurs on the molecular level that causes this frustrating disease. However, we do know that psoriasis is caused by one or more gene mutations that trigger cells in the immune system to attack the skin.

But not everyone with these mutations gets psoriasis. Here are six environmental factors that can trigger a psoriasis flare:

1. Skin Injury

Sometimes an injury to the skin can cause a psoriasis patch to form. This is known as the Koebner phenomenon. It also occurs in other skin diseases, including eczema and lichen planus. It can take 2 to 6 weeks for a psoriasis lesion to develop after an injury occurs. Injuries that can trigger a flare include:

  • Abrasion (even mild abrasion)
  • Increased friction from clothing or skin rubbing against the skin in folds, such as in the armpits or under the breasts
  • Sunburn
  • Viral rashes
  • Drug rashes

2. Weather

Weather is a major factor in psoriasis flares. Exposure to direct sunlight, which usually occurs during warmer months, often improves the rash. But cold, short days during winter months typically makes the rash worsen.

3. Stress

Psychological stress has long been understood as a trigger for psoriasis flares. How exactly it occurs is unclear. Studies show that not only can a sudden, stressful event trigger a rash to worsen, but the daily hassles of life can also trigger a flare. Another study shows that people who were categorized as "high worriers" were almost two times less likely to respond to treatment compared with "low worriers."

4. Infection

Infections caused by bacteria or viruses can cause a psoriasis flare. Streptococcal infections that cause tonsillitis, strep throat, tooth abscesses, cellulitis, and impetigo can cause a flare of guttate psoriasis in children. Human immunodeficiency virus (HIV) does not increase the frequency of psoriasis, but it does increase the severity of the disease.

5. Low Vitamins

Low calcium levels have been reported as a psoriasis trigger. Oddly enough, even though medications made from vitamin D are used to treat psoriasis, low levels of vitamin D do not trigger a flare.

6. Drug Triggers

There are quite a few different drugs that are known to either worsen psoriasis or induce a flare-up. Here are a few to look out for:

  • Chloroquine - Used to treat or prevent malaria.
  • ACE inhibitors - Used to treat high blood pressure. Examples include monopril, captopril, and lisinopril.
  • Beta-blockers - Also used to treat high blood pressure. Examples include lopressor and atenolol.
  • Lithium - A medication used to treat bipolar disorder.
  • Indocin - An anti-inflammatory medication used to treat a variety of conditions, including gout and arthritis.

Additionally, corticosteroids, which dramatically improve many cases of psoriasis, are potentially hazardous. Even though medications such as prednisone or solumedrol are effective for many, abruptly stopping the drug or rapidly tapering off of it can also trigger a flare-up.

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Article Sources
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