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How cough syrup can lead to cavities

Coughs, colds and flu can make your life miserable. And like most people, you’ll probably reach for an over-the-counter medication to ease your symptoms. But did you know that your spoonful of medicine could probably add “tooth decay” to its list of possible side effects?

Many cough drops and liquid medications contain a variety of ingredients that make your teeth more susceptible to decay:

Ingredients in cough syrup that can harm your teeth

  • Sugars. Ingredients such as high fructose corn syrup and sucrose contribute to decay when the bacteria in your mouth feed on the sugars, breaking them down and forming acids that attack the enamel of your teeth.
  • Acids. Ingredients such as citric acid can wear down the enamel of your teeth. In addition, some antihistamine syrups contain low pH levels and high acidity, which can be a dangerous combination for your teeth.
  • Alcohol. The addition of alcohol in some popular cold and cough syrups can have a drying effect on the mouth. Saliva helps to naturally rinse the sugars and acids away from your teeth — so with less saliva present, the sugars and acids remain in the mouth even longer, leading to greater risk for decay.

These risks can be magnified if you take medication before bedtime. Because you produce less saliva while you sleep, sugar and acids remain in contact with your teeth longer, increasing your risk for decay.

What's the remedy?

There are things you can do to lessen the effects of the sugars and acids in liquid medication.

  • Take liquid medication at mealtimes instead of bedtime so your mouth produces saliva to rinse away the sugars and acids.
  • Brush your teeth with fluoride toothpaste after taking medication. If the medication is very acidic, wait 30 minutes before brushing to allow your enamel to harden.
  • If you can’t brush, rinse your mouth well with water or chew sugar-free gum after taking liquid medication.
  • Take calcium supplements or use topical fluoride after using liquid medication.
  • If it’s available, choose a pill form of the medication instead of syrup.

Last updated October 18, 2021


The oral health information on this website is intended for educational purposes only. Always consult a licensed dentist or other qualified health care professional for any questions concerning your oral health.