No doubt, Saliva protects your teeth. It reduces the population of bacteria and amount of decay causing acids in your mouth. It also contains substances important for re-mineralization (repair of tooth enamel that have been damaged by acids).
Yet, continuous use of some medications causes damage to the teeth, while some others left in the mouth at night or while sleeping may damage the teeth or soft tissues(such as gum, palate) inside the mouth. Many of them reduce the flow of saliva and cause a condition known as “Xerostomia” (dry mouth). This condition significantly increases the risk of tooth decay.
Dry mouth causes an increase in the population of bacteria and amount of decay causing acids in the mouth, promoting tooth decay and cavities.
Examples of these medications are
Antihistamines: Clopheniramine (Piriton), Loratidine
Cancer medications: Chemotherapy drugs generally cause dryness of the mouth
Some Anti-hypertensives: Propanolol, Amlodipine
Antacids (chewables & suspensions): Relcer gel, Mist.mag, Danacid
Some analgeics such as Tramadol.
See also: Could you be deficient in Zinc?
Certain medications also contain sugars like glucose or fructose, which could cause bacteria on your teeth. Some cough syrups, chewable tablets and lozenges fall into this category. Prolonged exposure, such as repeated overnight exposure, can then cause or promote tooth decay.
Some other medications contain chemicals which may be acidic. These types of medicines can cause acid on your teeth. Prolonged exposure, such as repeated overnight exposure, can then erode the enamel of your teeth. Aspirin is one example of an acidic medication. It can produce a chemical burn on the soft tissues (gums, palate or cheeks) inside your mouth and can dissolve away small amount of enamel.
While certain medications are life-saving and cannot be avoided, practical steps can be taken to protect your teeth and prevent further damage. Take sips of water several times throughout the day to keep your mouth and body hydrated.
A good rule of thumb is that the last things that touch your teeth before sleeping should be dental floss and a toothbrush. So, take your nightly medications, then floss and brush.