Canker Sores

Jul 8, 2017

By Trevor Shewfelt, Pharmacist at the Dauphin Clinic Pharmacy

"How much money do I have left on my card?" Eric was calling from Fudd's Convenience Store with the phone he borrowed from his mother. He had just got his first debit card from Catalyst Credit Union. He was very excited. His sister had given him money for helping her deliver the Dauphin Herald and Parkland Shopper and he had deposited it into his account. There were so many things he was going to buy with this new magic card. After saying he was out of money, Eric he said he was off to the movie theater and hung up. Eric didn't answer when Doris called back. Why is it we let kids borrow cell phones if they don't answer when we call? Anyway, I drove down to Fudd's to see if there was some outstanding bill, or an upset kid or something. The very nice cashier told me that Eric had used his new debit card properly, and had enough cash in his pocket to make up the difference for the snacks he bought. As I was driving back home, Doris called and said she'd checked online and Eric had spent all his Dauphin Herald money. And she'd got a hold of Eric. He had walked almost the whole way to the movie theatre, but would have no way to buy a ticket when he arrived.

Sometimes the pain of not having money to buy something you want is a teachable moment. Sometimes the pain is just a pain in the mouth. A common cause of pain in the mouth are 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 NSAID's may also make canker sores happen more often.

Canker sores 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 not 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 100's.

To prevent canker sores, first try to minimize trauma to the inside of your mouth. Chew slowly and carefully to try to avoid accidental self biting. Avoid sharp-edged food like hard candies, hard toast, crackers and potato chips. If it feels like your teeth or dental appliances have sharp spots that are hurting the inside of your mouth, see your dentist.

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.

If your canker sores don't go away in less than 2 weeks or if they are very painful, you should see your dentist. They may prescribe an oral paste with the steroid triamcinolone in it to decrease the pain and inflammation. They could prescribe a numbing mouth wash called tantum or benzydamine to reduce mouth pain. They could also ask the pharmacist to compound a tetracycline mouth wash. Tetracycline is an antibiotic. As a mouth wash it can reduce canker sore pain and size of the sore. However, like other antibiotics, it has potential side effects like oral thrush, skin rash, sore throat and stained teeth.

I drove down to the movie theater. Eric, Brodie and two girls had just arrived on foot. The girls were smart enough to have their own money to buy movie tickets, popcorn, and drinks and went in ahead of Eric and his buddy. Eric was still blissfully unaware he had walked 45 minutes across town but had no way to pay for movie tickets. He had originally deposited enough Herald money into his account to treat him and his buddy to popcorn and a movie. But he had spent all his money before he made it to the theater. Debit cards are not magical money creation machines. Or at least that is what Eric should have learned. I think what he learned was if you call Mom then Dad will drive to wherever you are, buy your movie tickets and whatever else you need to bail you out of a jam. Why is it when other people parent, their children have teachable moments, but mine are just a pain in the ….. mouth?

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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