Cold sores overview
What is a cold sore?
A cold sore is a skin infection that is caused by a virus called herpes simplex 1.
How did I get a cold sore?
The herpes simplex virus that causes cold sores is very common and very contagious. Cold sores can be passed from one person to another through skin-to-skin contact. They can also be spread in saliva or mucus that comes from the nose and mouth. You can pick up the virus when you kiss or share drinking or eating utensils, towels or toothbrushes with someone who already has a cold sore. Most people get the virus when they are young.
How do cold sores feel?
It takes 4 or 5 days after being infected for the cold sore virus to have an effect. Sometimes the first attack is very mild and you will hardly notice it. You may feel generally off-colour for 4 or 5 days because the virus can affect your whole body. You can get swollen glands (lymph nodes) under your jaw and a fever. You may feel a bit sick or not enjoy eating.
Blisters or cold sores will then break out around your mouth. They usually go away on their own in 7 to 10 days. After the first attack, the virus spends most of its time ‘hiding’ in the nerves that go to the skin or eyes. From time to time, it is stirred up and travels to the same area around the mouth.
Some people only have one or a few attacks, while others have regular, painful attacks. The first sign that a cold sore is on the way is tingling and itchiness, usually around the lips or mouth, but also sometimes around the tongue, gums or the insides of the cheeks or eyes. Blisters then break out in the same spot and these later become dry and crusty.
What makes a cold sore worse?
The cold sore virus can be stirred up by too much sun, cold or wind, having your period, or things such as stress, alcohol, colds, flu or fevers that make the body less able to fight off invaders.
What makes a cold sore better?
- Resisting the temptation to lick, poke or prod at the area.
- Keeping it dry and clean so it doesn’t get infected. An alcohol solution can help. If it gets infected, see your doctor.
- Putting ice wrapped in a damp, clean cloth on the sore.
- Avoiding acidic food such as grapefruit or lemons.
- Protecting your skin from sun and wind.
- Using over-the-counter remedies recommended by a doctor or pharmacist may help symptoms and relieve pain.
How can my doctor help me with my cold sores?
Once you have the cold sore virus, you can never get rid of it. The aim of treatment is to make the attacks less uncomfortable. In addition to the above, your doctor may prescribe an antiviral ointment, but it needs to be used very early in the attack (as soon as you feel the tingling or itchiness starting). Antibiotics may be needed if the cold sore gets infected.
If you have frequent recurrent attacks of cold sores, or a severe bout, your doctor may prescribe an oral antiviral medicine.
What happens if a cold sore isn’t treated?
Cold sores usually heal without a scar within 2 weeks, but are likely to come back.
Protect yourself and others from cold sores
When you have a cold sore:
- change your toothbrush and towels regularly and don’t use those belonging to other people;
- don’t share eating utensils or kiss anyone, particularly babies, as cold sores are much more severe for them; and
- wash your hands frequently and avoid rubbing your eyes to stop the virus spreading. Remind children with cold sores about this.
Last Reviewed: 06 August 2007
