Cold sores are fairly common & usually nothing to worry about. Here’s everything you need to know, from causes to treatment options

One in five people in the UK get occasional cold sores around the lips and mouth. Cold sores themselves are not usually harmful, and often resolve on their own. But if you’re worried about them, we’ve gathered together some top tips to help treat cold sores and avoid spreading them to others. 

What are cold sores?

These are skin lesions around the mouth and nose. They start off as blisters and later become ulcers which crust over.

Cold sores are caused by the herpes simplex virus (HSV), a common virus which is spread through direct skin-to-skin contact. It's common to get infected in your childhood after kisses from a family member with cold sores.

What can trigger a cold sore?

There are two types of HSV that cause cold sores: type 1 and type 2. HSV-1 typically causes cold sores, while HSV-2 tends to cause genital herpes. However, if the HSV-2 comes into contact with the mouth, it can present as cold sores. Equally, the HSV-1 virus can cause genital herpes if it spreads to the genital area.

How can I avoid spreading cold sores to others?

Since the virus requires contact with the skin to spread to others, it's a good idea to avoid doing the following things when you have cold sores:

• Kissing
• Sharing lip balms, cutlery, face towels and other items
• Having oral sex 

It's important to be especially careful around people who have compromised immunity when you have cold sores. This includes people receiving chemotherapy.

You should also take special care around babies who may get neonatal herpes if they get infected – don't kiss babies or young children if you have a cold sore. Neonatal herpes is a very severe condition which can affect the organs and is sometimes life-threatening.

What are the symptoms of a cold sore?

The first signs of a cold sore can include a tingling or burning sensation on the lips or nose. Within 24 hours, you may start to see fluid-filled blisters form around the mouth. Blisters may weep until they scab over, dry and heal, which usually takes around a week. 

The first time you get cold sores is often different from follow-up infections. It can either be very mild with just a few sores over the tongue, or more severe, involving more sores which are spread over a larger area.

Why do I keep getting cold sores?

Once you’ve had cold sores, it's more likely that you'll get them again. This is because, even after your sores disappear, the virus lies dormant in a nearby nerve and has the potential to cause the infection again.

There are some situations and triggers that can cause your cold sores to reappear. These include:

• Having your period
• Getting sick, such as a common cold or the flu
• Stress
• Strong and direct sunlight

How to soothe cold sore symptoms

Cold sores heal on their own after a few days. However, there are some things you can do that may help with the discomfort until you get better:

• Eat soft, cool foods such as cold soups, jelly and yoghurt. Avoid acidic or salty foods as they'll make your sores sting
• You may find brushing your teeth too painful, so instead, use an antiseptic mouthwash
• Don't pick or touch sores to avoid spreading the virus
• Wash your hands thoroughly after touching your sores
• If you find that sunlight aggravates your symptoms, apply a moisturising sun cream to your face to protect and prevent sores

If you use contact lenses, make sure that you wash your hands well with soap and water before handling lenses. The virus can be transferred to the eyes through contaminated lenses, causing a serious eye infection. It may be helpful to use daily lenses or to wear glasses until your cold sores are better. If you think you may have developed an eye infection, speak to your GP.

How can I treat cold sores?

Once you are infected, there's no cure for cold sores. However, some medicines can relieve your symptoms and help to cut a bout of cold sores short. Ask your pharmacist for advice on which medicines are best suited to you:

• Take a painkiller like paracetamol to help control pain from cold sores – ask your pharmacist for advice as not all painkillers are suitable for everyone
• Use a gel that contains choline salicylate to help soothe symptoms. Children under 16 years shouldn't use these gels because they can cause Reye's syndrome, which is a rare but serious condition
• Antiviral creams, like aciclovir cream, can be applied five times a day, usually for up to 10 days. Wash your hands with soap and water before and after applying the cream. Dab the cream on the sores and avoid rubbing the lesions. Make sure to read the patient information leaflet for detailed instructions on how to use this medicine. Apply the cream as soon as you start to feel a tingling. It's thought that using a cream as soon as you get symptoms can help to reduce the length of the episode.

Antiviral tablets are also available but they're not often used to treat cold sores. You'll need a prescription from your GP to get these. Visit your GP if you're concerned about your cold sores, they will be able to advise on the most suitable treatment for you.

Boots Antiviral Cold Sore Cream – 2g Tube

Use this aciclovir cream at the tingle or blister stage to help treat cold sores and promote healing. Always read the label.

Bonjela – 15g

This cooling gel contains choline salicylate to help provide pain relief from cold sores. Always read the label.

When should I see my GP for cold sores?

Very often, you'll be able to manage symptoms on your own. However, make an appointment with your GP if you:

• Get cold sores for longer than 10 days
• Are worried about a cold sore or if it's very large or painful
• Are pregnant
• Have a weakened immune system due to an existing condition or have recently had chemotherapy
• Have swollen, painful gums and sores in the mouth

Next steps

• Avoid aggravating cold sores with hot or spicy foods 
• You can take painkillers or apply a suitable oral gel to help soothe the pain
• Avoid passing on cold sores to others by avoiding kissing or sharing objects which touch the mouth. This is especially important with babies and other vulnerable people
• Understand when you should visit your GP for advice


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