Thank you! Please check your email to confirm your sweepstakes entry. Click here to close this window

Are Canker Sores Contagious

By - Bad Breath Expert

Many people who have a canker sore in the mouth want to know, “Are canker sores contagious?” While canker sores are not pleasant and can be uncomfortable, they are not contagious. This means that a canker sore cannot be transmitted by bodily contact from a person who has one. Contagious is when someone has something that can be spread person to person and canker sores are not transmitted this way.

What are canker sores?

A canker sore is a small aphthous ulcer that can appear on the linings of the lips and cheeks and inside the mouth. Normally you will only have one at a time, however sometimes they can occur in a small group. These ulcers start off as a small red bump, which then ends up bursting and leaving a small open sore to heal. While these sores are not always pleasant and can be uncomfortable, they are not contagious.

canker sore

Canker sores should not be confused with a cold sore, which is normally on the outside of the mouth and usually appears when there is a virus in the body. These types of sores are highly contagious and those with one should not kiss or share any food or drink. A canker sore can be very sore and can come about on anyone for several different reasons -- during menstruation, smoking, and eating certain foods -- but are not normally associated with a virus as a cold sore is. Normally when someone gets canker sores it is often because of his or her genetics and he or she may have a close family member that has also suffered with them. Personal oral hygiene is also determining factor in the development of canker sores. TheraBreath provides many products that help treat canker sores. These products are listed below.

What causes canker sores?

There are many different reasons why someone might get a canker sore, but as stated above it tends not to be related to any viral infection. Some canker sore sufferers have these causes to blame:

  • Poor Diet
  • Genetics
  • Stress
  • Hormonal Imbalance
  • Food Allergies
  • Bacteria
  • Iron or Vitamin Deficiency

Are canker sores contagious?

Unlike cold sores, canker sores are not contagious. These open sores that are found on the tongue and inside the mouth cannot be transferred to someone else and are not caused by any type of physical interaction, including any mouth-to-mouth kissing or sharing food and drinks. Canker sores are not a form of any viral infection and therefore cannot be spread to another person no matter how close physical contact is.

While canker sores are not contagious, it is smart to not have any physical mouth-to-mouth interaction. Since there are bacteria in the mouth and saliva, it can bother the canker sore and infect it. This might result in having the sore become more painful and bothersome along with lasting much longer. However, you can rest assured that although they can provide some discomfort and are not too physically attractive to look at, they are not contagious.

Canker Sores versus Cold Sores

While a canker sore is normally inside the mouth and is not contagious, a cold sore is quite the opposite. Cold sores are small red blisters that appear along the mouth and face (most commonly on the lips and side of the mouth) and are highly contagious. These blisters are also normally caused by a virus such as Herpes Simplex (oral herpes). Since cold sores are so contagious, a person with one should not come into close contact with another person while these lesions appear.

In order to decipher whether a person has either a cold sore or a canker sore, they might need to have a medical doctor examine it to be sure. Both of these sores may look similar, so it can be hard to notice the difference by just looking at them. However, a person can take safe precautions such as no interaction with another partner physically until the sore is completely gone. Click here to read more about Canker Sore vs Cold Sore.

Canker sore treatments

Fear not if you find yourself with a canker sore. There are several ways to treat a canker sore including some homemade treatments and over the counter medicines. They can take anywhere from a few days to a few weeks to diminish but the treatments will be able to help ease the pain and reduce the redness and size. Most of the over the counter treatments have eucalyptol and menthol in them which helps to numb the sore.

Washing your mouth out with hydrogen peroxide and water can help shrink and clean the sore. Salt water is also an option for those looking for at home treatments, especially when it is mixed with baking soda.

Another thing to consider is your diet while you have a canker sore. Stay away from any foods that are spicy or acidic. Any fruit juices can also make the canker sore more painful and should not be consumed while the sore is apparent.

Top-Selling Canker Sore Treatment Products
TheraBreath Toothpaste TheraBreath Basic Kit TheraBreath Complete Starter Kit
$10.50
Used with our oral rinse, this toothpaste stops bad breath instantly.
$21.00
Containing one rinse, one toothpaste, and one tongue scraper, this kit will get you started with the basic TheraBreath regimen.
$75.00
Everything you need to get started with the TheraBreath system. Enough supplies for about two months of use!

How to prevent canker sores

Anyone who has had a canker sore knows how painful they can be, not to mention a nuisance when it comes to eating or drinking certain things, especially anything acidic. Prevent canker sores easily by using the right toothpaste and oral rinse. Most toothpastes have an ingredient called sodium lauryl sulfate (SLS) that helps create foam when you are brushing your teeth, but doesn’t hold a benefit to brushing and can cause canker sores or irritate them.

Use a toothpaste without SLS to help prevent these sores from ever occurring so you won’t need to worry about any future treatment. TheraBreath Fresh Breath Toothpaste is a specialty toothpaste that does not include SLS. This all natural toothpaste has no dyes, artificial flavorings or sugar so it will never irritate the mouth and can help keep it canker sore free.

By keeping your mouth clean, eating a balanced diet, and practicing stress relief tactics such as meditation and yoga, you have a great chance of not seeing a canker sore anytime soon. However, when you have canker sores in your DNA due to genetics, sometimes even doing these procedures won’t help prevent canker sores. If one does arise, there is no reason for alarm. Since canker sores are not contagious, a person with one can go on with their everyday lives without any worry. If a sore lasts for more than a few weeks or continues to come back, it might be a good idea to get it checked by a medical professional. From there, the doctor might be able to prescribe something topical that can be placed on the sore and help diminish it.


TheraBreath products are used by millions of people worldwide. Click here to read some of their success stories.