What causes cold sores?
Cold sores are caused by the herpes simplex virus. There are two types of herpes simplex virus, called type 1 and type 2. Either type can be caught on any part of the body. The lips and genitals are the most common places. This page is about facial sores – which can also be called fever blisters, facial herpes or herpes labialis.
Does it make any difference which type I have?
On the face, herpes simplex type 1 is more likely to recur than type 2. So if you are getting repeated cold sores, then you probably have herpes simplex type 1.
How are cold sores caught and passed on?
You catch cold sores by being kissed by someone who has cold sore virus on their mouth. You might have caught it the other day – or maybe when you were a child, perhaps by being kissed by a relative. Oral sex is also a common way of passing on cold sores from one person’s genitals (genital herpes) to another person’s mouth – or vice versa.
The virus can be caught on ordinary skin such as the hand/fingers if there is broken skin which can allow entry. It is called a whitlow on the fingers. This will be on just one finger.
Cold sores are only caught by direct skin contact, with the affected area. They are not caught through sharing cups, cutlery, towels, lipstick, etc. (unless there is warm pus on the item). Experts are definite about this, though this fact is sometimes ignored by unreliable sources on the Internet and elsewhere.
You cannot give cold sores to someone who already has them.
Will cold sores make me ill?
Sometimes, when you first catch cold sores, you can have ulcers inside the mouth and throat as well as, or instead of, the usual sores on the lip. You may have a fever and other flu-like symptoms. A painkiller can help, such as aspirin, ibuprofen or paracetamol. Always follow the instructions on the packet.
How common are cold sores?
Cold sores are very common. In Britain, about seven in ten people have caught one of the viruses that cause them. Worldwide figures are similar. However, most people don’t know, as only one in three who catches the virus will notice any symptoms. Whichever herpes simplex type you have, you could catch the other type in the same place or elsewhere. Infection with a second type often goes unnoticed or the symptoms that appear may be very mild. This is because the antibodies that have developed to fight the first virus also help to control the other one.
What are cold sores like?
- First a small red patch appears
- A blister or cluster of blisters develops.
- The blister bursts, leaving a raw area.
- The raw area begins to heal and scab.
- Scabs may crack when you move your mouth and this will delay healing. Try to keep the skin moisturised – see our self-help suggestions below, or try the lemon balm salve (LomaProtect) or cream (Lomaherpan).
- Do not pick at the scab – this will delay healing.
- Wash your hands before and after applying cream.
- The sore will heal itself without scarring, usually in about 7-10 days.
How can cold sores reappear?
The virus stays in a nerve junction near the spinal cord and may sometimes reappear, from time to time. Other herpes viruses also hide away and may recur; for example, chickenpox/shingles and glandular fever, but they do not cause cold sores.
Can my cold sore appear anywhere else?
This is unlikely. If you caught your cold sore on your lips, it might reappear elsewhere on your face, but it cannot reappear elsewhere on your body. You make antibodies in response to the virus, and they prevent you from spreading it to another area. They also make it unlikely that you will catch it again.
Will I know if a cold sore is about to come back?
You may feel an itch, tingle or shooting pain first. Repeat cold sores are usually much milder than the first ones.
What triggers a recurrence?
Triggers vary from person to person: try to find out what causes your outbreaks so that you can try to prevent them. Common reasons for recurrences are illness, stress, tiredness, being run down, having a period, too much alcohol or ultraviolet (UV) light from the sun or sunbeds.
Our suggestions for preventing cold sores?
A healthy lifestyle can help to keep your immune system in good shape and make cold sores less likely. Avoid any triggers you have identified and:
- Get enough sleep
- Improve your diet. New research has found that one reason for too many cold sores is a lack of selenium. One Brazil nut per day gives a very good dose of selenium.
- You might like to try an immune support product. The two capsules shown on our shop page have been tested by us, using our members as volunteers. Both of these products helped two thirds of the people taking them. (This is a good result – don’t believe anyone who claims 100% success rate!)
- If sunlight or sunbeds trigger your outbreaks, use a good quality sun block, especially on the lips. It is best to prevent the cold sore from coming out. Once it is there, treatments can only shorten the duration of the cold sore. As well as the general rules above, you might want to try melissa cream – see below.
Can I take anything to stop getting frequent cold sores?
Antiviral tablets may be prescribed for cold sores. If you get an unacceptable number of outbreaks, talk to your doctor. You can see the dosage that is given for preventing recurrences on our ‘treating herpes‘ page (3rd bullet point).
Antiviral tablets are a more effective way of treating and preventing cold sores than antiviral creams. Also, see treatment and self-help suggestions sections below.
What treatments can I buy at chemists’ shops?
Some creams contain anaesthetics (e.g. lidocaine 5%, benzocaine, prilocaine or tetracaine) which will stop any soreness if a cold sore breaks through. You can see a list of some of these anaesthetic creams. [Also, a small trial has shown that a lidocaine 5% ointment prevented outbreaks in one in three of the people testing it and shortened the outbreaks that did break through from 5 days to 2 days.] No prescription is needed: politely tell the pharmacist to check the list if he/she says otherwise. If they ask “What for?” you are allowed to say “I would rather not tell you.” This can be handy, because you don’t want them to try to get you to buy other cold sore products.
Antiviral creams containing aciclovir are widely available. If you start using them at the ‘tingle’ stage, they can shorten the outbreaks by 12 percent (from an average of 7 days down to 6 and a quarter days).
A newer antiviral cream, Fenestil, contains penciclovir 1% and has a similar benefit.
What self-help suggestions may help prevent cold sores?
Some people with cold sores have said that applying a wrapped ice pack to the area for 90 minutes prevents the outbreak, but take care not to cause frostbite. (This idea has not been medically tested.) A salve and a cream containing lemon balm mint (melissa officinalis) have been shown to prevent outbreaks if used at the tingle stage. This plant contains molecules which prevent the virus from getting into the skin cells. LomaProtect is a herbal salve made with an extract of lemon balm mint.
What useful tips may speed up the healing process?
Some people with cold sores on the face have told us that these ideas helped them – but they have not been medically tested:
- Cold used tea bags applied hourly can help. The terpenes in tea draw moisture out of the cells.
- Geranium oil, tea tree oil – diluted – and lavender oil – will soothe.
- Keep the skin soft and moist with an unscented product such as Vaseline (petroleum jelly) to prevent scabs from cracking and coming off.
Are cold sores ever serious?
Medical attention is very rarely needed for cold sores. In rare cases, a facial cold sore may affect one eye (not both). This will be a recurrence, after a previous cold sore infection. If one eye is tingling and sore or red, a GP or an optician can check. They will do a fluorescein stain to see if the cause is herpes simplex virus. If it is, you may be referred to a specialist eye hospital.
A few unlucky people get them too often. Antiviral tablets can be prescribed by a doctor – or see our self-help ideas above.
People with areas of broken skin (like eczema) should be careful during their first infection as sores may spread over the area of broken skin.
People with weakened immune systems (e.g. on cancer drugs, or following an organ transplant) may need medication to prevent cold sores.
Newborn babies should not be exposed to cold sore virus – if you get cold sores, don’t kiss babies!
Why be self-conscious…
Your cold sores will seem bigger to you than they appear to anyone else! Ignore advertising campaigns which try to make people with cold sores feel ashamed, embarrassed or worried. Advertising which makes people feel bad about themselves is designed to sell more treatment.
Cold sores are common and most people are not bothered about them.
This page was last reviewed on 31-07-2023