HealthInfo West Coast-Te Tai Poutini

Cold sores

Kōmaoa

Cold sores are small blisters on your lip or around your mouth. They are caused by the herpes simplex virus. Cold sores are also known as facial herpes and fever blisters.

If you get the virus, it stays in your system for the rest of your life. It hides in your nerve cells and can become active again. Most people do not get cold sores again, or only get a few, but some have regular flare-ups.

Symptoms of cold sores

Cold sores often start with a tingling, itching or burning sensation around your mouth. Small fluid-filled sores then appear, usually on the edges of your lip.

Treating cold sores

Cold sores usually go away by themselves in 7 to 10 days without treatment.

If you start using it early enough, povidone iodine 10% ointment (Betadine) may make a cold sore go away faster. You can buy this cream at most supermarkets and pharmacies without a prescription. Or you can get a prescription from your general practice team.

Antiviral tablets may be used for severe cold sores. If you get a lot of cold sores, you could talk to your general practice team about taking antiviral tablets daily. This can help prevent future cold sores.

  HealthInfo recommends the following pages

• DermNet NZ – Herpes simplex

  Information about herpes simples, the virus that causes cold sores.

• The New Zealand Herpes Foundation – Facial herpes

  Information about facial herpes (cold sores), including how you catch it and how it is treated.

Written by HealthInfo clinical advisers. Last reviewed May 2025.

Sources

Page reference: 180573

Review key: HICOS-180573