Canker Sore Causes and Prevention

Canker sores are painful conditions that can also be difficult to treat. However, were you aware that these bothersome mouth ulcers have a source that is just as surprising? It's the herpes simplex virus that we're discussing here! Continue reading for in-depth information on the causes of canker sores and preventative measures, which will finally allow you to get rid of these annoying suckers.

What Are Canker Sores?

Canker sores are painful ulcers that grow inside your mouth and are known by this name. Even though these unsightly mouth ulcers can manifest in any part of your mouth, the back of your throat is typically where they are discovered. This is because saliva is most concentrated in the back of your throat. Even though they can show up in any part of your mouth, this is the most common location where they are found. Stomatitis, also known as cold sores and aphthous ulcers, and stomatitis (inflammation of the mouth) are all names that are occasionally used interchangeably to refer to this disease.

Canker sores are caused by a virus called herpes simplex —the same virus that causes cold sores and genital herpes. Although smaller than cold sores, canker sores tend to be more painful and usually last longer (lasting at least 10-14 days).

Canker sores are categorized according to their appearance. The two main types of canker sores are −

  • External − These include the classic, shallow open sores that crust over as they heal. Commonly found inside the mouth, external cankers can sometimes be on the outside of your lips and gums. They are typically not very painful and heal relatively quickly.

  • Recurring − These are the canker sores that tend to appear frequently. These sores are more profound and painful, often leaving behind a permanent dimple in your lip.

The herpes simplex virus is also responsible for several other skin problems besides canker sores, including cold sores on the face, shingles (a rash caused by the virus that travels down your nerves), and genital herpes.

Canker Sore Causes and Symptoms

Although a virus causes canker sores, it is most commonly triggered by a physical injury to your mouth. Canker sores have several frequent causes, including −

  • Biting your cheek or tongue

  • long-term chewing of hard sweets or ice

  • Eating extremely spicy food (cayenne peppers are notorious offenders)

  • Eating acidic foods like lemons and oranges can make canker sores worse. It is best to avoid these foods when you have canker sores.

Sucking on lemon products or hard candy items can also cause canker sores, but reading the labels before purchasing them is essential. Lemon products are often high in citric acid, which worsens your canker sore symptoms. The same goes for any hard candy.

Canker sore triggers vary from person to person and can be difficult to pinpoint. Cold air and windy weather can dry your mouth, increasing your chances of picking up the virus. Stress has also been known to aggravate painful cold sores.

Canker mouth sores are often brought on by general exhaustion. The risk of getting the virus that causes cankers is higher for those with compromised immune systems. There are foods called immune boosters; if you suffer from canker sores frequently, consider eating them.

Canker Sore Symptoms & Diagnosis

Once you notice a tender, painful ulcer in your mouth, it is essential to identify what type of sore it is-external or recurring. Recurring canker sores are the ones that leave behind a permanent scar and occur most often. They are typically found on the lower lip or inside your cheeks. Recurring sores are also the type that frequently appears during periods of stress.

External canker sores, on the other hand, are found outside your mouth or lips and tend to heal faster than recurring ones. They are much less painful as well.

Symptoms of canker sores include −

  • A small, round sore that is either bright red or white. This sore usually has a greyish-yellow circle around it. An ulcerated area inside your mouth (not on the outside) is incredibly tender to the touch and sometimes painful to swallow. It may take about ten days for this area to heal. A headache or general feeling of malaise (weak, tired, and achy) often comes with canker sores.

Talk to your dentist if you're unsure if you have a canker sore. He will be able to tell you the difference between chronic canker sores and other oral infections and conditions such as thrush. Another good way to determine the cause of your sore is by examining it under a microscope. If it's an infection or condition other than an STD, you should be able to see irregular shapes in the cells that make up your sore.

Canker Sore Treatments

Although it's impossible to cure the herpes simplex virus, you can treat canker sores with medications and home remedies to ease your pain and discomfort. You can also do several things to prevent the onset of new sores.

To find a treatment for your canker sore that works best for you, consider what triggers the onset of these sores (biting your cheek on accident, sucking on a lemon) and try to avoid those stimuli whenever possible. Some foods help fight off cold sore outbreaks.

Antiviral Medications

Antiviral medications often treat canker sores and other herpes simplex-related infections. Antivirals such as acyclovir (Zovirax) and valacyclovir (Valtrex) are available in pill or cream form and help prevent outbreaks by lessening the severity and duration of the virus. They don't stop the virus, but they make it less likely that you'll acquire it together. It's best to take these medications at the first sign of an outbreak for the best results.


If you're suffering from canker sores, try to avoid worsening conditions. These include being run down and stressed. If treatment for your sore is required, see your doctor as soon as possible. If you experience recurring canker sores, they're most likely caused by stress, not the herpes simplex virus. If your sore does have an STD origin, talk to your doctor about treatment options for genital herpes and cold sores.

Updated on: 15-Feb-2023


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