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Cold sores: causes, symptoms and treatment

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What is a cold sore?

A cold sore is an infection that appears on your skin as small painful blisters. These usually develop on your lips, but they can appear on other parts of the face and body. They’re very contagious especially when the blisters have burst.

What causes cold sores?

Cold sores are caused by the herpes simplex virus. This virus has two types, Type 1 (HSV-1) is transmitted by oral-to-oral contact, whereas type 2 (HSV-2) is a Sexually Transmitted Infection (STI).

Most people contract the virus when they’re young and after they have come into contact with someone who has the virus. The virus then stays in your skin for your whole life; you may not know that you have it until cold sores start to appear. You may not notice any symptoms until you are older.

What triggers a cold sore?

There are a variety of environmental and physical factors which can bring on an outbreak of cold sores, these are different from person to person. Once you have identified your triggers you might be able to put some steps in place that will help you to avoid these situations in the future.

  • Stress – these emotions can wear down your immune system making you more vulnerable to infections.
  • Fatigue – being tired can also affect your immune system. When your body is worn out you’ll become vulnerable to a cold sore outbreak as your body cannot fight off the virus as well as it usually could.
  • Weather – cold weather can dry out lips and cause cracks and sores to appear. To avoid this can you protect your skin from the wind and cold with lip salves and moisturisers. On the other hand, too much exposure to the sun can damage the skin, including your lips. Using an SPF enriched lip balm or wearing a wide-brimmed hat can help you to protect your skin.
  • Hormonal changes – for women your menstrual cycle can also trigger a cold sore outbreak, this can be easily tracked and then you can be better prepared for an outbreak.
  • Cold or flu – when your immune system is already compromised cold sores you are more likely to get a cold sore.

Cold sore stages and symptoms

The symptoms of cold sores often appear in stages. During these stages cold sores are at their most infectious.

Stage Symptoms
Stage 1  You can feel tingling and itching around 24 hours before the blisters appear.
Stage 2 You will notice fluid filled blisters break out on your skin.
Stage 3 The blisters will burst and ooze fluid; consequently, they will form a painful sore.
Stage 4 The sores will dry out and a scab will form over them. During this stage the cold sores will feel itchy, and the skin will begin to crack. 
Stage 5 The scabs will fall off and the cold sore will heal.


How long do cold sores last?

Cold sores usually take up to 10 days to heal completely, however there are measures you can take to speed up the process. You can apply a cold compress to your cold sores as this may help to decrease the redness around the sore, but ultimately, they will not disappear overnight.

How to treat cold sores

There is a whole range of cold sore treatments that you can buy in your local pharmacy and online to help get rid of your cold sore. You can take paracetamol or ibuprofen to ease the pain and calm the swelling. But you may also want to use cold sore patches to conceal the cold sore and reduce the amount of scabbing that you may experience.

Cold sore patches

Cold sore patches act like a second skin to offer eight hours of protection and aid the body’s natural healing process. Patches can also help to reduce the risk of contamination from the wound; however, it is important that you don’t kiss anyone while the cold sore is present, even if you are wearing a patch.

Cold sore creams

You can also treat your cold sore with creams which can help to soothe the tingling feeling while controlling the infection. A tingling feeling will tend to be noticeable before the blisters break out on the skin; these will then ooze fluid and create painful sores. Topical lotions and creams can offer soothing relief by moisturising the sores and keeping them under control. Your cold sores will then scab over as they begin to heal and eventually disappear.

Things to avoid when you have a cold sore

Cold sores are very contagious, especially when the blisters are present, to stop from spreading the virus there are certain things you should avoid:

  • Touching your cold sore
  • Kissing
  • Sharing anything that comes in contact with your cold sore, like toothbrushes, cutlery and lipsticks
  • Having oral sex until your cold sore has completely healed

If you have a cold sore, it is important that you don’t kiss new born babies as this is very dangerous and can lead to neonatal herpes. Their immune system is not as developed as an adult’s and so they may not be able to fight off the virus.

Can you pop a cold sore?

This is one of the worst things you can do to a cold sore. Not only will it hurt but by squeezing the sore you can help the infected fluid inside to spread to another part of your mouth or lip. Also, the infection can be transmitted to your eyes, fingers, other body parts and even other people. This could make your next outbreak of cold sores much more severe.

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