Chickenpox is a common illness that mainly affects children and causes an itchy, spotty rash.

Most children will catch chickenpox at some point. It can also occur in adults who didn't have it when they were a child.

It's usually mild and clears up in a week or so, but it can be dangerous for some people, such as pregnant women, newborn babies and people with a weakened immune system.

This page covers:

Symptoms

How to treat it at home

When to get medical advice

How you catch it

Possible complications

Frequently asked questions (FAQs)

Symptoms of chickenpox

The symptoms of chickenpox start one to three weeks after becoming infected.

The main symptom is a rash that develops in three stages:

  • stage 1: spots – red raised spots develop on the face or chest before spreading to other parts of the body
  • stage 2: blisters – over the next few hours or the following day, very itchy fluid-filled blisters develop on top of the spots
  • stage 3: scabs and crusts – after a further few days, the blisters dry out and scab over to form a crust; the crusts then gradually fall off by themselves over the next week or two

Chickenpox is contagious until all the blisters have scabbed over, which usually happens about five or six days after the rash appeared.

Read about the symptoms of chickenpox for more information and pictures of the different stages of the rash.

How to treat chickenpox at home

Chickenpox can usually be treated at home.

You or your child will probably feel pretty miserable and uncomfortable, but treatment can help relieve the symptoms.

The following can help:

  • take over-the-counter painkillers such as paracetamol to relieve fever and discomfort
  • use calamine lotion, moisturising creams or cooling gels to ease itching
  • tap or pat the skin rather than scratching it – it's important to avoid scratching because this can lead to further problems
  • drink plenty of fluids to stay hydrated

You should also take steps to stop chickenpox spreading, such as staying away from school or work until the last blister has scabbed over.

Read more about how to treat chickenpox.

When to get medical advice

Chickenpox is normally mild and gets better on its own. But some people can become more seriously ill and need to see a doctor.

It's a good idea to contact your GP or NHS 111 for advice if:

  • you're not sure if you or your child has chickenpox
  • your baby is less than four weeks old and has chickenpox
  • you develop chickenpox as an adult
  • the symptoms haven't started to improve after six days
  • you've been in contact with someone who has chickenpox (or you have symptoms) and you're pregnant, breastfeeding or have a weakened immune system
  • you or your child has signs of chickenpox complications, such as swollen and painful skin, difficulty breathing or dehydration

Also consider getting advice if you're originally from a country near the equator (the tropics) and you've been in close contact with someone who has chickenpox.

Chickenpox is much more common in adults from these areas and you may need treatment to help stop you becoming seriously ill.

How you catch chickenpox

Chickenpox is caused by a virus that spreads very easily to people who haven't had it before. If you have had it before, you'll usually be immune for life.

The infection is spread in the fluid found in chickenpox blisters and the droplets in the coughs or sneezes of someone with the infection.

You can catch chickenpox from:

  • contaminated surfaces
  • contaminated objects, such as toys or bedding
  • touching chickenpox blisters or the shingles rash
  • face-to-face contact with an infected person, such as having a conversation
  • being in the same room as an infected person for 15 minutes or more

Someone with chickenpox is infectious from one or two days before the rash appears until all the blisters have dried out and crusted over.

Possible complications

Most people with chickenpox will make a full recovery. But occasionally serious complications can occur.

These are more common in adults, pregnant women, newborn babies and people with weakened immune systems.

Possible complications include:

  • a bacterial skin infection – this can cause the skin to become red, swollen and painful
  • a lung infection (pneumonia) – this can cause a persistent cough, breathing difficulties and chest pain
  • pregnancy problems – including the infection spreading to the unborn baby

Some people with chickenpox may develop shingles later in life. This is a painful, blistery rash caused by the chickenpox virus becoming reactivated.

Read more about the complications of chickenpox.

Chickenpox FAQs

Page last reviewed: 18/10/2016

Next review due: 18/10/2019