What causes psoriasis, and what can trigger a flare?

How do immune and genetic factors contribute?

Evidence indicates that immune activity and several genes contribute to inflammation and altered skin-cell growth. A family history can increase susceptibility, but not everyone with related genes develops psoriasis.

Psoriasis is not the patient's fault and should not be reduced to one behaviour. Care aims to control inflammation, reduce identifiable triggers, and monitor effects on skin, nails, joints, and overall health.

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Is psoriasis contagious?

No. Psoriasis is not contagious and cannot be passed from one person to another.

Several skin conditions can resemble psoriasis. When the diagnosis is unclear, seek a clinical assessment rather than deciding from appearance alone.

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What may trigger a psoriasis flare?

Triggers are not the same for everyone and may change over time. Track events that repeatedly align with flares rather than trying to avoid every item on a general list.

• Scratching, cuts, tattoos, sunburn, or other skin injury.
• Some infections, especially sore throat associated with guttate psoriasis in some people.
• Stress, which may relate to flares but is not the sole cause.
• Cold or dry weather for some people.
• Smoking and alcohol use.
• Some medicines or abruptly stopping certain medicines.

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Should you stop a medicine if you think it triggered psoriasis?

Do not stop a prescribed medicine on your own, especially one that must be tapered. Abruptly stopping some medicines may worsen psoriasis. Record the medicine name, dates of starting or changing it, and changes in the rash, then speak with the prescriber and dermatologist.

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Does stress cause psoriasis?

Stress may be one trigger or make symptoms harder to manage, but it does not explain the whole condition and should not be used to blame a patient. Stress support complements medical care; it does not replace treatment or follow-up.

[2, 5]