Hives (Urticaria) factsheet

Introduction

Hives, also called urticaria, are a type of red, raised, itchy skin rash. Hives happen when the body releases histamine from your child’s skin cells. Histamines help fight illness and infection.

Hives can happen for different reasons, including:

  • illness or infection
  • allergic reactions – when the body reacts to something that is usually harmless
  • autoimmune conditions – when the body’s immune system attacks healthy cells
  • skin irritation – from things like chemicals, medicine, stress, or heat

Hives are common in children. They may appear and disappear over several hours, and they can move around the body.

 Signs and symptoms

Hives look like a red, raised rash. The raised parts of the rash are called wheals.

Wheals come in different sizes, from tiny spots to large patches. They can feel itchy and hot, and they often appear in groups. 

Hives may appear quickly, spread, then fade or move to a new spot on the body. Each group of hives can last from a few minutes to a few hours.

Along with hives, your child might also have:

  • a runny nose
  • watery eyes
  • angioedema - swelling in the hands, feet, lips, or around the eyes.

Diagnosis

A doctor can usually diagnose hives by looking at the skin.

Acute hives

Acute hives last a few days and are often caused by illness, infection, or allergies.

  • hives from allergies often appear 1 to 2 hours after contact with the allergen
  • hives from an infection, like a virus, may appear 1 to 2 weeks after your child is sick.

Sometimes, the cause of acute hives is unknown. Allergy tests are usually not needed for acute hives.

Chronic hives

Chronic hives last longer than 6 to 8 weeks. Allergies do not cause chronic hives, and the cause is often unknown. In rare cases, an autoimmune condition may trigger chronic hives.

The doctor may order a blood test to help find the cause of chronic hives.

Physical urticaria

Physical urticaria is hives caused by physical triggers such as:

  • pressure or touch
  • sweating
  • heat, cold, or sunlight
  • stress
  • certain chemicals or skin irritants.

Physical hives may show up within 5-10 minutes of a trigger and usually last about 30-60 minutes before fading.

Treatment

Treatment depends on the type of hives and your child’s health.

The most common treatment is an oral antihistamine, a medicine that blocks histamines to reduce symptoms. Antihistamines can help reduce the number of wheals on your child’s skin and relieve symptoms like: 

  • swelling
  • runny nose
  • watery eyes.

Antihistamines are generally safe to use, but it’s important to check with your doctor to see if they work for your child. 

Children who do not respond to antihistamines or who have chronic hives may need to see a specialist, such as:

  • an allergist – allergy specialist
  • a dermatologist – skin specialist
  • an immunologist – immune system specialist
  • a dietitian – nutrition specialist who manages diet.

 Management

Hives and antibiotics

Some children have hives while taking antibiotics for an infection. Hives are usually caused by the infection, not the antibiotics.

If you are concerned, your child’s doctor can arrange a test in a hospital to check for an antibiotic allergy.

Hives and other medications

Certain medications can make hives worse, including:

  • aspirin
  • codeine
  • non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen

Paracetamol is generally safe, but check with your child's doctor if you are unsure.

Disclaimer

This factsheet is provided for general information only. It does not constitute health advice and should not be used to diagnose or treat any health condition.

Please consult with your doctor or other health professional to make sure this information is right for you and/or your child.

The Sydney Children’s Hospitals Network does not accept responsibility for inaccuracies or omissions, the interpretation of the information, or for success or appropriateness of any treatment described in the factsheet.

© Sydney Children’s Hospitals Network 2025


This factsheet was produced with support from John Hunter Children's Hospital.