what causes psoriasis flare ups

June 28, 2026

Psoriasis flare-ups are usually caused by a mix of immune, lifestyle, and environmental triggers that “wake up” an already overactive immune system in the skin. Your genes set the stage, but day‑to‑day triggers often decide when you actually flare.

How psoriasis works in the background

Psoriasis is a chronic autoimmune condition where the immune system mistakenly attacks the skin, speeding up skin cell growth so plaques build up. You can go through calmer phases and then suddenly flare because something has provoked that immune response.

Researchers often group triggers into extrinsic (outside your body) and intrinsic (inside your body, like hormones or stress). Knowing which ones fit your life is one of the most powerful ways to reduce how often and how badly you flare.

Major common psoriasis flare-up triggers

1. Stress and emotional strain

Mental or emotional stress is one of the most commonly reported flare-up triggers.

When you are stressed, your body releases stress hormones that can disrupt immune balance and drive inflammation in the skin.

Many people notice plaques appear or worsen during work pressure, family crises, money worries, or after poor sleep.

Calming practices like meditation, yoga, breathing exercises, and support groups can reduce stress-related flares over time.

2. Infections and illness

Throat infections (especially strep throat), colds, flu, bronchitis, ear infections and even COVID‑19 have all been linked to psoriasis flares.

A classic example is guttate psoriasis, which can suddenly appear after a strep throat infection, especially in children and young adults.

Flares often show up 2–6 weeks after the infection, even after you feel generally better.

Treating infections promptly and keeping vaccines up to date can help reduce illness‑related flares.

3. Skin injury (Koebner phenomenon)

Cuts, scrapes, insect bites, tattoos, sunburns, shaving injuries, and even scratches can trigger new plaques at the exact site of injury.

This reaction is called the Koebner response and is quite common in people with psoriasis.

New lesions may appear around 10–14 days after the skin trauma.

Gentle skin care, sun protection, and avoiding unnecessary trauma (like aggressive scratching or picking) can lower this risk.

4. Weather and climate

Dry, cold weather is a frequent trigger because it dries out the skin and can worsen inflammation.

Warm, sunny weather often improves psoriasis, but sunburns and constant air‑conditioning dryness can still cause flares.

Rapid seasonal changes (like moving from humid summer to dry winter) may also provoke a flare.

Using thick moisturizers, humidifiers indoors, and sunscreen outdoors helps protect against weather‑related flares.

5. Certain medications

Some medicines are known to trigger or worsen psoriasis in susceptible people.

Common examples include:

Lithium (used for some mood disorders).

Beta‑blockers (used for blood pressure and heart conditions).

Some antimalarials and synthetic antimalarial drugs.

Certain antibiotics and newly developed drugs or vaccines in some cases.

Some anti‑inflammatory medicines including ibuprofen, plus ACE inhibitors used for high blood pressure.

Never stop a prescription on your own, but do tell your doctor or dermatologist if your skin worsened after starting a new medication.

6. Alcohol and smoking

Drinking excessive alcohol is a well‑recognized trigger and is associated with more severe psoriasis and poorer control.

Smoking is also a major lifestyle risk factor; it can increase the chance of developing psoriasis and can worsen existing disease.

Cutting down or quitting both alcohol and cigarettes can meaningfully improve flares and long‑term outcomes.

7. Hormonal changes

Hormonal shifts, particularly in women, can affect psoriasis activity.

Puberty, pregnancy, and menopause are common times when plaques may either worsen or sometimes temporarily improve.

Tracking skin changes through these phases can help you and your clinician anticipate and manage flares.

8. Metabolic and internal factors

Obesity, metabolic syndrome, and insulin resistance are linked with more frequent or severe psoriasis flares.

Changes in the gut and skin microbiome (dysbiosis) are emerging internal triggers that may influence inflammation and flare risk.

Weight management, regular exercise, and a balanced diet may not cure psoriasis, but they can make flares less intense and improve treatment response.

9. Lifestyle and environmental exposures

Exposure to pollution and environmental irritants may contribute to flare‑ups in some people.

Very dry indoor air, harsh soaps, hot showers, and fragranced products can strip moisture and irritate the skin, encouraging plaques.

Switching to gentle cleansers, lukewarm showers, and fragrance‑free moisturizers often makes a visible difference.

Quick trigger overview (HTML table)

Here’s a compact view of what causes psoriasis flare ups and how they tend to show up:

html

<table>
  <thead>
    <tr>
      <th>Trigger type</th>
      <th>Examples</th>
      <th>How it can cause a flare</th>
    </tr>
  </thead>
  <tbody>
    <tr>
      <td>Stress</td>
      <td>Work pressure, family conflict, poor sleep [web:3][web:5]</td>
      <td>Raises stress hormones, overstimulates immune system, speeds skin cell turnover [web:3][web:7]</td>
    </tr>
    <tr>
      <td>Infections</td>
      <td>Strep throat, colds, flu, bronchitis, ear infections, COVID‑19 [web:1][web:5]</td>
      <td>Immune system activation spills over into skin, causing new plaques (often 2–6 weeks later) [web:1][web:5]</td>
    </tr>
    <tr>
      <td>Skin injury (Koebner)</td>
      <td>Cuts, scrapes, bites, tattoos, sunburn, shaving injuries [web:1][web:5][web:9]</td>
      <td>Triggers plaques exactly where the skin was damaged, usually after 10–14 days [web:5][web:9]</td>
    </tr>
    <tr>
      <td>Weather</td>
      <td>Cold, dry air; indoor heating; AC; sunburn [web:3][web:5][web:6]</td>
      <td>Dries and irritates skin or burns it, making existing plaques worse or causing new ones [web:5][web:6]</td>
    </tr>
    <tr>
      <td>Medications</td>
      <td>Lithium, beta‑blockers, antimalarials, some antibiotics, ACE inhibitors, some vaccines [web:7][web:9]</td>
      <td>Can directly trigger new psoriasis or worsen controlled disease in susceptible people [web:7]</td>
    </tr>
    <tr>
      <td>Alcohol & smoking</td>
      <td>Heavy drinking, regular cigarette use [web:7][web:9]</td>
      <td>Increase systemic inflammation and make psoriasis harder to control [web:7][web:9]</td>
    </tr>
    <tr>
      <td>Hormonal changes</td>
      <td>Puberty, pregnancy, menopause [web:9][web:7]</td>
      <td>Hormone shifts alter immune activity and skin behavior, changing flare patterns [web:7][web:9]</td>
    </tr>
    <tr>
      <td>Metabolic factors</td>
      <td>Obesity, metabolic syndrome, insulin resistance [web:7]</td>
      <td>Raise chronic inflammation and are linked to more frequent or severe flares [web:7]</td>
    </tr>
    <tr>
      <td>Environmental & skin care</td>
      <td>Pollution, harsh soaps, hot showers, fragranced products [web:5][web:6][web:7]</td>
      <td>Irritate or dry the skin, lowering its barrier and enabling plaques to form or worsen [web:5][web:6][web:7]</td>
    </tr>
  </tbody>
</table>

What people are saying lately (forums & “latest” vibe)

Many recent clinic blogs and patient communities in 2024–2026 focus on stress plus infections as the “double hit” that sets off flares after the pandemic years.

Forum posts often mention sudden guttate‑style breakouts after strep throat in teens and young adults, echoing what dermatology sources describe.

There is also growing discussion around new drugs and vaccines as “emerging” triggers, but experts still stress that benefits usually outweigh risks and that decisions should be made with a dermatologist.

You’ll also see a lot of practical threads where people trade tips about moisturizing routines, diet changes, and stress‑management hacks that helped them reduce how often they flare.

How to figure out your personal triggers

Keep a simple flare diary
Note dates of flares, stress levels, illnesses, new meds, weather changes, and anything unusual with your skin (sunburns, bites, tattoos).

Look for patterns over 1–3 months
You might notice, for example, that you often flare after big deadlines, winter cold snaps, or every time you get a sore throat.

Review with a dermatologist
They can help distinguish true triggers from coincidences and adjust your treatment plan to buffer you against unavoidable triggers.

Tackle the “easy” triggers first
Moisturizing daily, protecting your skin from injury and sunburn, managing stress, and moderating alcohol or smoking usually give visible benefits fastest.

Quick TL;DR

Most psoriasis flare ups are caused by a combination of stress, infections, skin injuries, weather changes, certain medications, alcohol, smoking, hormonal shifts, metabolic issues, and environmental irritants acting on an already sensitive immune system. Learning your own pattern of triggers—and working with a dermatologist to limit or buffer them—is one of the best ways to keep flares fewer, shorter, and less severe.

Information gathered from public forums or data available on the internet and portrayed here.