Learn how to diagnose and prevent recurrent flare-ups of this pesky herpes simplex virus.
Medically reviewed by Dr Juliet McGrattan (MBChB) and Based on a text by Dr Flemming Andersen
Unsightly blister on your lip? Don’t panic! A cold sore outbreak can feel like the end of the world, especially if you have an important meeting or hot date on the agenda, but they are perfectly common and nothing to be alarmed about. But how do you treat cold sores and is there a way to prevent future outbreaks? We investigate:
What are cold sores?
Cold sores are caused by the herpes simplex virus (HSV) and usually clear up on their own within 10 days. They are contagious, but don’t let that stop you carrying on with your day. Just try not to smooch anyone until it goes away.
Cold sore symptoms
Cold sores often start with a tingling sensation around the mouth or lips, before forming small blisters. These are characterised by groups of fluid-filled sacs which appear on red swollen areas of the skin or on the mucous membranes. The areas can be tender and painful. The blisters heal without scarring but have a tendency to recur.
There are two types of herpes simplex virus:
• Herpes simplex: HSV-1
The most common type, this usually causes cold sores (oral herpes). Approximately 80 per cent of the adult population have antibodies against HSV-1 in their blood.
• Herpes simplex: HSV-2
This usually causes genital herpes. But both types can infect any area of the skin or mucous membranes. Around 25 per cent of the adult population have antibodies against HSV-2.
Cold sore treatment
Some antiviral medications are available over-the-counter from a pharmacy and others on prescription. They come in two different forms:
- Creams containing aciclovir (eg Zovirax cold sore cream): applied directly to the area.
- Oral medication: recurrent attacks can be treated by anti-HSV agentsin pill form.
The treatment should be started as soon as the first symptoms appear. Antiviral creams containing aciclovir can reduce the length of the outbreak and the infectious period.
They are most effective the earlier they are used when a cold sore is starting to develop, so make sure you keep your medication at hand, so it can be applied at the earliest sign of a sore.
Cold sore causes
How do you catch cold sores? 1 in 5 people in the UK suffer from recurring cold sores. The HSV-1 virus is transmitted by close personal contact, such as kissing.
The development of cold sores differs from person to person. Some people will have few or no reactivations while others have recurrent outbreaks.
1 in 5 people in the UK suffer from recurring cold sores. The HSV-1 virus is transmitted by close personal contact.
If you are feeling run down or have a weak immune system, this can lead to a reactivation of the virus and a return of the blisters. Recurrences seem to become less frequent with age.
In rare cases, cold sores can also be caused by the herpes simplex virus type 2 (HSV-2), as a result of having oral sex with someone who has genital herpes.
Cold sore prevention tips
There are a few simple measures you can take to lessen the impact of cold sores, but if you do suffer from recurrent attacks, visit your GP to discuss the best course of action. In the interim, try the following:
✔️ Avoid direct contact with the sores. These can appear on every part of the body, including the fingers and genitals.
✔️ Wash your hands after touching your lips.
✔️ Avoid picking the sores, as this can spread the virus to other parts of the body or result in a bacterial infection of the sores.
✔️ The body’s defences can be strengthened by a healthy lifestyle. Eat a varied diet, exercise regularly and get enough sleep.
✔️ Menstruation, fever and exposure to sunlight can cause a reactivation in some people, so using a sunblock may help to prevent a reactivation.