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Frequently asked questions about urticaria

Short, clear answers compiled by Asoke Skin Hospital. If your symptoms don't match an answer here, consult a dermatologist directly.

Reviewed by the dermatology team of Asoke Skin Hospital

Published · Last reviewed

What causes urticaria?

Urticaria wheals appear when mast cells in the skin release histamine, making the skin swell and itch. Triggers differ between people — infections, medicines, foods (in genuine allergy), stress, or physical stimuli such as cold and pressure. In most chronic urticaria no clear external cause is found.

What causes urticaria? Common triggers explained

How long do hives last?

Each wheal usually fades within 24 hours, though new ones may appear. Acute urticaria mostly clears within days to a few weeks. If it keeps coming and going beyond 6 weeks it is chronic urticaria, and you should see a dermatologist.

What is urticaria (hives)? Symptoms and how it differs from other rashes

Is urticaria contagious?

No. Urticaria is not caused by a transmissible germ. Touching, sharing items, or being near someone with hives cannot give you urticaria.

Living with chronic urticaria while keeping life normal

What should I avoid eating with urticaria?

There is no blanket forbidden-food list that applies to everyone. Avoid only foods proven to cause you genuine allergy. Alcohol and NSAID painkillers can flare the rash in some people. Cutting out many food groups without medical advice does not speed recovery.

Living with chronic urticaria while keeping life normal

Can stress cause hives?

Stress alone is not a direct cause, but it is a common flare factor that can make an existing rash more frequent or itchier. Managing stress and sleep is part of caring for urticaria.

What causes urticaria? Common triggers explained

Why do hives appear at night?

In the evening skin temperature shifts, and with fewer distractions the itch is felt more sharply; warm bedding also plays a part. If itching wakes you often, tell your doctor so the timing or dose of your medicine can be adjusted.

What causes urticaria? Common triggers explained

Can chronic urticaria be cured?

It can be controlled, and in many patients symptoms can settle on their own over time. The goal of treatment is to keep symptoms quiet with a regular antihistamine; for hard-to-control cases doctors have further guideline options such as biologic medicines.

Living with chronic urticaria while keeping life normal

Is urticaria dangerous?

Mostly not, even though it can be very disruptive. The exception is when the rash comes with tongue or throat swelling, difficulty breathing, or near-fainting — signs of a severe allergic reaction that needs a hospital immediately.

Which urticaria needs a doctor — and which needs the hospital right now

Is it safe to take antihistamines every day long-term?

Modern antihistamines are designed for continuous use, and the international guideline recommends taking them regularly while the disease is active, under a doctor's follow-up. Do not stop abruptly as soon as the rash quiets down, because it often returns.

How is urticaria treated? Taking antihistamines the right way

Is urticaria different in children?

The mechanism is the same, but acute urticaria in children is more often linked to viral infections and mostly resolves on its own. If the rash keeps recurring or comes with swelling, see a doctor.

Which urticaria needs a doctor — and which needs the hospital right now

Do I need blood tests or allergy tests?

Not everyone. Ordinary acute urticaria does not need them. For chronic urticaria doctors usually check a few basic blood tests, and choose allergy testing only when the history genuinely points to a specific cause.

How doctors diagnose urticaria — are blood tests or allergy tests needed?

Where should I get urticaria treated?

If the rash is recurrent, chronic, or affecting daily life, see a dermatologist directly. Asoke Skin Hospital is a specialized dermatology hospital with dermatologists available every day on a walk-in basis. Branch details and opening hours are on the hospital's main website.

Which urticaria needs a doctor — and which needs the hospital right now

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