A cold sore is a type of infection caused by the herpes simplex virus that usually forms on the lips or skin around the mouth. Symptoms typically include a burning pain followed by small blisters or sores. The first attack may also be accompanied by fever, sore throat, and enlarged lymph nodes.
Do you have a cold sore?
A cold sore usually starts with a tingling, itching or burning feeling. Over the next 48 hours, fluid-filled blisters form. Cold sores should start to heal within 10 days, but may spread and be irritating or painful while they heal.
Some people find that certain things can trigger a cold sore, such as another illness, prolonged exposure to sunlight or menstruation.
| Symptoms |
|---|
| Painful red spot on the face that fills with pus |
| Blister on the lip or inside the mouth |
| Red sores or blisters on the face that develop a honey-coloured crust |
A pharmacist can recommend:
-Creams to ease pain and irritation
-Antiviral creams to speed up healing
-Cold sore patches to protect the skin while it heals
-Electronic devices from pharmacies that treat cold sores with light or lasers. Some people find these helpful, but there haven’t been many studies to find out if they work.
If you regularly get cold sores, use antiviral creams as soon as you recognise early symptoms. They don’t always work after blisters appear.
Things you can do yourself
Cold sores take time to heal and they’re very contagious, especially when the blisters burst.
| Dos | Don’ts |
|---|---|
| Eat cool, soft foods | Do not touch your cold sore (except when applying cream) |
| Use an antiseptic mouthwash if it hurts to brush your teeth | Do not eat acidic or salty foods |
| Wash your hands with soap and water before and after applying cream | Do not rub cream into the cold sore – dab it on instead |
| Avoid anything that triggers your cold sores | Do not kiss anyone while you have a cold sore and especially babies, as they are at risk for Neonatal Herpes |
| Drink plenty of fluids to avoid dehydrationDo not share personal items that come into contact with your cold sore (such as creams, utensils or lipstick) | Do not share personal items that come into contact with your cold sore (such as creams, utensils or lipstick) |
| Use sunblock lip balm (SPF 15 or above) if sunshine is the trigger | Do not engage in oral sex until your cold sore heals completely – the virus also causes genital herpes |
| Take paracetamol or ibuprofen to ease pain and swelling (liquid paracetamol is available for children) |
You should see your personal doctor if:
-The cold sore hasn’t started to heal within 10 days
-You’re worried about a cold sore or think it’s something else
-The cold sore is very large or painful
-You have swollen, painful gums and sores in the mouth (gingivostomatitis)
-You’re pregnant – there’s an increased risk of neonatal herpes
-You have a weakened immune system – for example, because of chemotherapy or diabetes
Treatment from your personal doctor
Your personal doctor may prescribe antiviral tablets if your cold sores are very large, painful or keep coming back.
Newborn babies, pregnant women and people with a weakened immune system may be referred to hospital for advice or treatment.
Why cold sores come back
Cold sores are caused by the herpes simplex virus (HSV).
Once you contract the virus, it lies dormant in your body for the rest of your life. Sometimes it causes a cold sore.
Most people are exposed to the virus during childhood. It doesn’t usually cause any symptoms until you’re older. You won’t know if it’s in your skin unless you get a cold sore.
