Cold sores

How do I know if I've got a cold sore?

You'll get a tingle on or around your lips, then a little blister (a fluid-filled blob). Then a sore patch after the blister bursts and oozes. Then a crust. Nice. But thankfully, they are almost always gone within a week or so.

What causes them?

If I say Herpes, promise not to scream? Cold sores are caused by a virus called Herpes Simplex Virus (HSV). The same virus can give us genital Herpes.

Cold sores on the privates are unpleasant. And sexually transmitted. But cold sores on the mouth are usually less of a problem. About 70% of us get these at some time or another. Babies, nuns, headmasters. It's nothing to do with sex.

How do I get it?

HSV is very contagious. The first time we get cold sores (usually when we're still a kid) it's from kissing someone who has one. So thanks, Mum/Gran/Auntie Janice. Chances are, it was you. If cold sores come back, we haven't caught HSV again. It's our own HSV causing the trouble. HSV sleeps in our bodies, ready to wake up again from time to time.

How do I stop cold sores coming back?

Sometimes it's impossible to keep the HSV sleeping. And for 20% of us, the cold sores come back over and over again.

But here's a list of common culprits to avoid:
Sunlight/strong wind
Stress
Being run down/unwell

I have a cold sore! Help!

Don't pick. It'll last longer.
Take some paracetamol. Cold sores can hurt.
Get some cold sore cream from the chemist (ask your pharmacist). The sooner we get that on ourselves the better, so don't wait till the crust stage.

See your doctor if:

Your cold sores won't go away.
Your eyes starting itching/going red, too.
You have cold sores anywhere other than your lips. That goes double if they're anywhere near your bum.

Further help and advice

NHS cold sore advice

Written by Dr Melissa Sayer

Last updated 3rd July 2007

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