Urticaria (Hives)

An itchy rash of raised welts that come and go. It can be triggered by allergies, infections or unknown causes.

SkinAllergyLast updated: 21 October 2026

Quick Summary

Primary Symptoms

Itchy, raised, red or skin-coloured welts that appear and fade within hours, sometimes with swelling of lips or eyes.

Common Treatments

Antihistamines, avoiding known triggers, and specialist treatment for long-lasting hives.

Risk Factors

Allergies to foods or medicines, infections, insect stings, heat, pressure and stress.

OverviewSymptomsCausesTreatmentFAQ

Overview

Hives happen when cells in the skin release histamine. Acute urticaria lasts under six weeks; chronic urticaria lasts longer.

Hives with breathing difficulty or throat swelling may be anaphylaxis, an emergency.

Symptoms

Itchy welts

Raised, moving rash.

Swelling

Of lips, eyes or face (angioedema).

Comes and goes

Individual welts fade within 24 hours.

Anaphylaxis

Breathing difficulty or throat swelling: call 112.

Causes & Risk Factors

Biological Causes

Histamine release from mast cells in the skin, triggered by allergy, infection or unknown causes.

Key Risk Factors

  • Allergies Foods, medicines and insect stings.
  • Infections Viral infections often trigger hives in children.
  • Physical triggers Heat, cold, pressure and scratching.

Management & Treatment

01. Antihistamines

Such as cetirizine or fexofenadine.

02. Avoid triggers

If known.

03. Specialist care

For chronic hives not controlled by antihistamines.

Frequently Asked Questions

Is hives contagious?
No.
Do I need allergy tests?
Sometimes, especially if a trigger is suspected.

Sources and further reading

Last updated 21 October 2026. For more detail, see these trusted health organisations.