Cold sores usually clear up on their own but until they go away they are contagious.
They can appear anywhere on the face and usually start off as a small fluid-filled blister before bursting and crusting over into a scab.
Certain things can trigger cold sores, such as an illness or cold weather but they should clear up within 10 days.
Creams can be recommended by your pharmacist to ease pain and irritation, but there is also a particular practice you should always make sure to go overtime before and after applying it.
As well as eating cool, soft foods and using an antiseptic mouthwash if it hurts to brush your teeth, the NHS recommends washing your hands with soap and water before and after applying cream.
You should also drink plenty of fluids to avoid dehydration, take paracetamol or ibuprofen to ease pain and swelling, and avoid anything that triggers your cold sores.
There are six things you should avoid though when a cold sore appears.
You should not eat acidic or salty food, touch your cold sore (apart from applying cream), rub cream into the cold sore – dab it on instead – and kiss anyone while you have a cold sore.
You should also avoid sharing anything that comes into contact with a cold sore (such as cold sore creams, cutlery or lipstick), and have oral sex until your cold sore completely heals – the cold sore virus also cause genital herpes.
Cold sores are caused by a virus called herpes simplex.
Once you have the virus, it stays in your skin for the rest of your life, but you will not know if it is in your skin unless you get a cold sore.
Indigo Faulkner, 18, claimed a liquorice balm helped to prevent her cold sores from returning.