8 Common Triggers of Psoriasis Flares

Identifying triggers is the first step in preventing symptoms

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Psoriasis is characterized by periods of worsening symptoms, known as flares, followed by periods of remission. The cause of flares is poorly understood, but factors such as skin trauma, cold weather, stress, and smoking are known to trigger their onset. This may be due to the sudden rise in inflammation prompted by the triggers, which reactivates the autoimmune response. This inflammation leads to the outbreak of symptoms, primarily skin lesions known as plaques.

This article discusses the most common triggers of psoriasis and how to manage them.


Living with Plaque Psoriasis

As frustrating as psoriasis can be, identifying and avoiding triggers can significantly reduce your risk of flares. Here are eight common triggers you should know about.

Skin Trauma

An injury to the skin can sometimes cause the reactivation of psoriasis symptoms. Known as the Koebner response, the phenomenon occurs not only with psoriasis but other diseases like juvenile idiopathic arthritis, lichen planus, and vitiligo.

Skin conditions that can trigger a psoriatic flare include:

  • Cuts and abrasions
  • Bruises
  • Friction from clothing
  • Vigorous scratching or shaving
  • Sunburn
  • Insect bites
  • Poison ivy or poison oak
  • Drug rash
  • Food allergies
  • Tattoos or piercings

Generally speaking, it can take anywhere from 10 days to two weeks for psoriasis symptoms to develop after a skin trauma.

To reduce your risk, treat any and all skin injuries immediately. Avoid scratching bites or rashes, using a topical ointment to reduce itchiness, if needed. If outdoors, use a bug repellant.

Sun and Hot Temperatures

The sun and heat are major factors for psoriasis flares. On the one hand, ultraviolet (UV) radiation from the sun can help ease symptoms as long as the exposure is limited. On the other hand, too much sun can overheat the skin and trigger a flare.

Extreme humidity is also problematic as it promotes sweating, another common trigger. Even taking a hot bath can trigger a flare by overheating the body.

To avoid sun- and heat-induced flares:

  • Wear sunscreen to reduce UV exposure (minimum 30 SPF).
  • Wear sun-protective clothing and hats when outdoors.
  • Dress lightly to avoid sweating.
  • Schedule outings for cooler parts of the day
  • Limit showers and baths to 10 minutes.
  • Use warm rather than hot water when bathing.

Cold, Dry Temperatures

Extreme cold, dry temperatures are another common trigger for psoriasis, making the disease all the more difficult to manage in winter months. The combination of cold and dryness promotes the cracking of the outer layer of skin, called the stratum corneum. This induces inflammation that triggers the psoriatic flares.

To avoid cold-induced flares:

  • Moisturize the skin regularly to lock in moisture and prevent cracking. This is especially true after bathing when skin oils are largely stripped from the body.
  • Keep indoor air moist with a humidifier set at 30% to 50%.
  • Choose warm baths over hot showers, adding bath oils, Epsom salt, or colloidal oatmeal to gently slough off dead skin and soothe itching.
  • Bundle up with soft layers when outdoors. Dressing in layers allows you to strip off clothing as you get hot, preventing sweating.
  • Keep well hydrated. Doing so helps keep the skin moist and hydrated.


Stress is known to be a trigger for psoriatic flares. Scientists are not sure why this is but theorize that the release of cortisol during stress increases systemic (whole-body) inflammation as well as body temperature, both of which act as independent triggers.

Stress has both a cause-and-effect relationship to psoriasis. While stress can trigger psoriasis symptoms, the appearance of lesions can induce stress, perpetuating psoriasis symptoms.

According to a 2014 review of studies from Europe, no less than 50% of people with psoriasis report that stress is a major disease trigger.

Routine exercise is one of the more effective ways to control stress. Mind-body therapies, such as meditation, yoga, guided imagery, and progressive muscle relaxation (PMR), can also help. If you're unable to cope, considering seeing a therapist or psychiatrist who can provide you the tools to better control your emotions.


Infections caused by a bacteria or virus are common causes of psoriasis flares. Certainly, at the front of the list are bacterial infections like strep throat and impetigo. Common viral causes include colds, influenza, mumps, and chickenpox.

Infection-induced flares are more common in children than adults, leading to a form of the disease known as guttate psoriasis.

HIV is another trigger that can induce psoriasis symptoms. While HIV doesn't increase the frequency of psoriasis, it can significantly increase the severity of outbreaks.

The best way to avoid flares is to treat any infection immediately. If you have HIV, starting HIV therapy can reduce the inflammation that drives acute flares.

Smoking and Drinking

Both smoking and drinking place undue stress on the body. If struggling to manage your psoriasis symptoms, these are two modifiable risk factors you can readily address.

According to a 2016 report in the journal Psoriasis, smoking not only doubles your risk of getting psoriasis but increases the severity and frequency of flares if you have it.

Smoking instigates immediate inflammation while constricting blood vessels throughout the body. To make matters worse, the risk of flares increases with the number of cigarettes you smoke per day.

With alcohol, the type of beverage you drink can play a part. According to a 2010 study in the Archives of Dermatology, non-light beer was more closely linked to psoriasis symptoms than either light beer, wine, or liquor. Heavy drinkers also appear to be at a greater risk.

To avoid psoriatic flares, the best thing to do is quit. This is especially true with smoking. With respect to alcohol, abstain or switch from regular beer to light beer or wine; reduce your intake to no more than two or three drinks per day.


There are quite a few drugs known to induce or worsen psoriasis symptoms. Theoretically, any drug has the potential to induce flare, but there some more likely to do so. These include:

  • Chloroquine used to treat or prevent malaria
  • ACE inhibitors used to treat high blood pressure
  • Beta-blockers also used to treat high blood pressure
  • Lithium used to treat bipolar disorder
  • Indocin (indomethacin), a prescription nonsteroidal anti-inflammatory drug (NSAID)

Corticosteroids sometimes used to treat psoriasis pose a serious risk if stopped abruptly. If this occurs, psoriasis symptoms can rebound, sometimes severely. To avoid this, corticosteroids may need to be tapered off gradually under the direction of a doctor if they are no longer needed.

The best way to avoid drug-induced flares is to let your rheumatologist know about any and all drugs you are taking, whether they are prescription, over-the-counter, or recreational. Mention all supplements as well.

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.

By Heather L. Brannon, MD
Heather L. Brannon, MD, is a family practice physician in Mauldin, South Carolina. She has been in practice for over 20 years.