Canker Sores

Sep 22, 2015

By Trevor Shewfelt, Pharmacist at the Dauphin Clinic Pharmacy

Another MS Bike tour to Clear Lake is in the books. Thanks again to all the volunteers and cyclists. This year my daughters friend, Allison Lunsted, cycled the whole 150 km for the first time. That is very impressive for a 13 year old. My daughter cycled back with us on the Sunday (only 75 km) because she had a hockey try-out on the Saturday. After her 3:40 minute ride on Sunday, she went to 2 different hockey practices on Sunday afternoon and evening. All that cycling and skating didn't seem to phase her much. After I rode on Sunday, I sat on the couch the rest of the day. The next day, I went out for my first skate of the season. I swear Monday Nite Hockey made every joint and muscle in my body hurt. I'm not a stellar hockey player at the best of times, but on Monday, I felt 80 years old. Apparently, my 13 year old daughter is just way tougher than me.

About the only place I didnt hurt after hockey was inside my mouth. A common cause of pain in the mouth is canker sores. Canker sores are little ulcers or erosions in the mouth. Their medical name is aphthous stomatitis or aphthous ulcers. A person usually gets their first canker sore between the ages of 10 and 20. Somewhere between 5-25% of the population gets them. Usually canker sores happen less often as we age. Women, people under 40, people with a family history of canker sores and people with upper-middle socioeconomic status tend to get canker sores more often.

We don't know what causes canker sores. There are probably lots of factors involved. We think the most common predisposing factors are trauma to the mouth (like biting your cheek, or the sharp corners of dental appliances rubbing) and stress. Certain foods may play a role including chocolate, coffee, peanuts, almonds, strawberries, cheese, and tomatoes. A poor diet may cause nutrient deficiency which makes canker sores more common. Some pain killing drugs like NSAIDs may also aggravate the canker sore situation.

Canker sore can be more than just annoying. Patients with more severe canker sores may have a lot of pain which can cause difficulty eating, speaking and swallowing. There are 3 types of canker sores: minor, major and herpetiform. Far and away the most common canker sores are the minor aphthae which account for 70-90% of the cases. Minor aphthae or minor canker sores are painful, small, round or oval ulcers which have clear raised edges with a red halo around them. They are smaller than 1 cm and usually have a whitish grey pseudomembrane over them. Minor canker sores occur singly or in groups up to 5 on the inside of the lips, cheek, floor of the mouth, underside of the tongue and the soft palate. Minor canker sores heal by themselves in 7-10 days, which is good, but that is more slowly than other oral wounds heal. Some people might feel some discomfort a few days before the actual canker sore occurs. Major aphthae or major canker sores are very uncommon. They are larger than 1 cm in size and can be in groups of more than 5. Herpetiform aphthous ulcers are the least common canker sore. They are multiple clusters of small pin-point ulcers than can number in the 100s.

We have several non-prescription options to treat canker sores. The dentists all seem to love salt water rinses several times per day. Dissolve a teaspoon of salt in 250 mL of warm water, rinse, spit and repeat. Do a salt water rinse several times a day. This helps to keep the canker sore clean which promotes healing. Local anesthetics like benzocaine and lidocaine, like in the product Orajel, will numb the pain of a canker sore for 20-45 minutes. For gels, ointments and pastes to work the best, dry the canker sore with a Kleenex before applying. Then apply with a Q-tip and avoid eating, drinking and speaking for 30 minutes. These analgesic gels can be used up to 4 times a day.

In addition to local anesthetics, you could use acetaminophen or tylenol pills. Don't use ibuprofen, naproxen or ASA. It is possible these NSAID's will make canker sores worse. Protecting pastes like orabase can also do a nice job of covering up the canker sore to make it more comfortable.

With appropriate treatment, the pain of canker sores can be managed. But the pain of a bruised ego is tougher to treat. I'm used to my little sister being able to kick my butt. She does triathlons, so she exercises a couple hours a day during the week and then goes for an 8 hour bike ride on Sundays. I've accepted that my little sister is way tougher than me. Now Emily has shown she can ride as far as me and then play hockey with no ill effects. My ego and I really didn't think my daughter would already be kicking my butt at age 13.

As always if you have any questions or concerns about these or other products, ask your pharmacist.

The information in this article is intended as a helpful guide only. It is not intended to be used as a substitute for professional advice. If you have any questions about your medications and what is right for you see your doctor, pharmacist or other health care professional.

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