from the Herpes Viruses Association
Registered charity no. 291657
What causes cold sores?
Cold sores are caused by herpes simplex virus. There are two types, called
type 1 and type 2. Either type can be caught on any part of the body: 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.
What’s the difference in the types?
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 an active facial cold sore. This
might have happened just the other day - or maybe when you were a child, perhaps by
being kissed by a relative.
Oral sex is a common way of passing on
cold sores from one person’s mouth to another person’s genitals
(genital herpes) - or vice versa.
Sometimes it will be caught on ordinary skin such as the hand or finger, if you kiss an are
where there is sore or broken skin which can allow entry.
Cold sores are only caught by direct skin
contact with the affected area, not through sharing cups, cutlery, towels, etc. Experts are clear about this,
though you may see the opposite being stated on the internet or in leaflets from others.
You cannot give cold sores to someone who already gets 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: 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 the virus that causes them.
However, most don’t know, as only one in five 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 and symptoms may be very mild.
This is because the antibodies that have developed to fight the first virus also help control the other one.
What are cold sores like?
- First a small red patch appears
- A blister or cluster of blisters
- The blister bursts, leaving a
- 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 suggestions below.
- Do not pick at the scab - this will delay
- 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 hides in a nearby nerve and can sometimes reappear later on.
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 sores appear anywhere else?
If you caught your cold sore on your lips, it can recur anywhere on
your face. It will not reappear elsewhere on your body. Your immune system will prevent you
from spreading it (or catching it again) on another area.
Will I know if it is about to come back?
You may feel an itch, tingle or shooting pain first. Repeat cold sores are usually much milder than the
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, menstruation, 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.
- If sunlight or sun-beds trigger your outbreaks,
use a good quality sun block, especially on the lips.
Can I take anything to stop getting frequent cold sores?
Antiviral tablets may be prescribed for cold sores. If you area getting an unacceptable number
of outbreaks, talk to your doctor. Antiviral tablets are a more effective way of preventing
cold sores than antiviral creams.
What treatments can I buy at chemists' shops?
Some products numb your skin and also may prevent the development of cold
sores. These are made with a topical anaesthetic (e.g. lidocaine 5% ointment), creams with
benzocaine, prilocaine or tetracaine which will stop any soreness if a cold sore breaks through. A
small trial has shown that a cream with lidocaine 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: ask the pharmacist to check the
list if he/she says otherwise.
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 prevent a 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.)
Using cream with lemon balm mint extract (melissa officinalis) early on has been
shown to prevent outbreaks. This plant contains molecules which prevent the virus from getting
into the skin cells. Lomaherpan is a herbal cream made with an extract of lemon balm.
What useful tips may speed up the healing process?
Some peole with cold sores on the face have told us that these ideas helped them -
but they have not been medically tested:
Are cold sores ever serious?
- Cold used tea-bags applied hourly can
- 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.
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 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 or
medicine can be prescribed by a doctor – or see our self-help ideas
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 who are immunocompromised (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 designed to stigmatise people with cold sores. Making
people feel ashamed, embarrassed or fearful is a common advertising tactic to encourage sales of treatments.
Cold sores are common and usually trivial. Most people are not bothered about them.
The Herpes Viruses Association
We have advice and information leaflets on all herpes viruses. These include
more suggestions to stop cold sores returning, and lots of help in dealing
with genital herpes simplex (cold sores on the genitals). For details of our
services and a list of leaflets, take a look at the membership form here.
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This page was updated and issued 24 November 2014 and will be reviewed no later than 24 November 2017.