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What are cold sores?
Cold sores are small blisters
around the mouth. They are also called fever blisters. They are caused by the herpes
simplex virus. The most common strain of the virus causing cold sores is herpes simplex
virus 1. It can be spread by kissing or sharing eating utensils or even sharing
Herpes simplex is not curable. But
may stay inactive for a long time.
What causes cold sores?
Cold sores are caused by the herpes simplex virus. Once this virus is
in you, it can cause outbreaks of cold sores. Cold sore outbreaks are often triggered by
exposure to hot sun, cold wind, a cold or other illness, a weak immune system, changing
hormone levels, or even stress.
What are the symptoms of cold sores?
Some people don’t have any symptoms
with the first attack. Others have flu-like symptoms and sores (ulcers) in and around
the mouth. Symptoms may occur a bit differently in each person. These are the most
Tingling of the lips, commonly felt before cold sores appear
Small blisters on the lips and mouth that enlarge, burst, then crust over
Itching, dryness, and irritation of the lips and mouth
Soreness of the lips and mouth
How are cold sores diagnosed?
Your healthcare provider can often diagnose cold sores by looking at
the sores. If the diagnosis is unclear, your provider may swab the sore and send it to
the lab for examination.
How are cold sores treated?
Cold sores can’t be cured. But, if
symptoms are severe, treatment may help ease some symptoms. Treatment may include:
Antiviral ointments such as acyclovir
and penciclovir to put on the sores are not very helpful.
Antiviral oral medicines such as
acyclovir, famciclovir, and valacyclovir may decrease the time the sores are present
or their severity.
Over-the-counter pain relief medicines
to put on the sores (topical) may help with symptoms. Anti-inflammatory medicines may
Cold sores take about 1 to 3 weeks
to heal. The first time they appear, they can take up to 3 weeks to heal. But when cold
sores return, they usually are less severe and take a week to heal if no medicines are
used. Antiviral medicines may help, but they work best if started with early symptoms
before a blister appears. Antivirals are usually not advised for otherwise healthy
people. Always talk your healthcare provider or dentist if the sore doesn't heal or
becomes worse as time passes.
Can cold sores be prevented?
If you have never had a cold sore, don't have skin-to-skin contact
with someone who has an active cold sore. If you have had a cold sore, you may prevent
or reduce the number of times they come back by finding out what triggers your
outbreaks. Then stay away from that trigger. For instance, if sun exposure is a
trigger, use sunscreen when in the sun. If you have outbreaks often, talk with your
healthcare provider. Starting treatment as soon as you know you are getting a cold sore
can help it heal faster.
The long-term use of oral antiviral medicines may prevent cold
sores, but the benefit is very small. This approach is usually used only for people who
get frequent and painful cold sores. Antiviral medicines to put on the sores appear to
not help prevent them or make them heal faster.
Key points about cold sores
Cold sores are small blisters around
the mouth caused by the herpes simplex virus.
Cold sores can be spread by kissing or sharing eating utensils or even sharing towels.
Tingling often happens before the
Cold sores cause small blisters on the lips and mouth that enlarge, burst, then crust over.
Early treatment can promote healing and reduce the time it takes a cold sore to heal.
Tips to help you get the most from a visit to your healthcare provider:
Know the reason for your visit and what you want to happen.
Before your visit, write down questions you want answered.
Bring someone with you to help you ask questions and remember what your provider tells you.
At the visit, write down the name of a new diagnosis, and any new medicines, treatments, or tests. Also write down any new instructions your provider gives you.
Know why a new medicine or treatment is prescribed, and how it will help you. Also know what the side effects are.
Ask if your condition can be treated in other ways.
Know why a test or procedure is recommended and what the results could mean.
Know what to expect if you do not take the medicine or have the test or procedure.
If you have a follow-up appointment, write down the date, time, and purpose for that visit.
Know how you can contact your provider if you have questions.
Online Medical Reviewer:
L Renee Watson MSN RN
Online Medical Reviewer:
Michael Lehrer MD
Online Medical Reviewer:
Rita Sather RN
Date Last Reviewed:
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