Cold sore - Preventing cold sores

It is not possible to prevent becoming infected with the herpes simplex virus or to prevent outbreaks of cold sores, but you can take steps to minimise the spread of infection.

Cold sores are at their most contagious when they rupture (burst) and remain contagious until they have completely healed.

Other people should avoid direct contact with your cold sore and the surrounding area until it has completely healed and disappeared.

However, if you or your child have a cold sore, there is no need for you to stay away from work or for your child to miss school.

Minimising the spread of infection

You can help minimise the risk of the cold sore virus spreading and cold sores recurring by following the advice below.

  • avoid touching cold sores unless you are applying cold sore cream – creams should be dabbed on gently rather than rubbed in as this can damage your skin further
  • always wash your hands before and after applying cold sore cream and after touching the affected area
  • do not share cold sore creams or medication with other people as this can cause the infection to spread
  • do not share items that come into contact with the affected area, such as lipsticks or cutlery
  • avoid kissing and oral sex until your cold sores have completely healed
  • be particularly careful around newborn babies, pregnant women and people with a low immune system, such as those with HIV or those having chemotherapy

Preventing cold sore outbreaks

If you know what usually triggers your cold sores, try to avoid the triggers. For example, a sun block lip balm (SPF 15 or higher) may help prevent cold sores that are triggered by bright sunlight.

Use an antiviral cold sore cream as soon as you feel the tingling sensation of a developing cold sore.

However, there is no benefit in using an antiviral cream continuously to try to prevent future cold sores. They cannot cure the virus and are only effective once the virus has been triggered.

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