9 Oral Side Effects From Medications

medication that cause dry mouth

What we put into our mouths—and bodies—plays a huge role when it comes to issues like tooth stains, cavities, and bad breath. And although most of us are already familiar with some of the oral side effects of medications, are there some medicines that cause tooth decay? Staining? Halitosis? Dry or burning mouth?

Absolutely. Medications that cause tooth decay are more common than most people realize.

The truth is, medication and teeth don’t always mix. Some types of drugs can send your oral health down a trail you don’t want to be on. Even though you’re taking medication to be healthier because of something else going on in your body, your mouth might not be really fond of what you’re putting into it.

1) Medications That Cause Cavities

Believe it or not, some medications can—if taken on a fairly frequent basis—raise your or your child’s risk of getting cavities.[1] Sugar and other types of sweeteners are frequently used in syrups. And syrups are extremely common for things like cold medicine, cough medicine, and basically any medication that your pediatrician prescribes to a child when they have to take it by mouth. Added flavorings or artificial sweeteners help make the medication a little more palatable.

Another example of when medications and teeth don’t mix is asthma meds. Inhalers and nebulizers are lifesaving and you need them to function. But the medication that’s being inhaled—through your mouth—can promote an oral environment that is more prone to developing cavities. So even if the medication isn’t technically the source of the cavity, it just makes it easier to get decay if you’re regularly using an inhaler.

One of the best things you can do after you use an inhaler or nebulizer is to rinse your mouth out with water. Don’t brush (it will just scrub the medicine around even more.) Rinse thoroughly and then brush later.

2) Medication That Causes Dry Mouth (Xerostomia)

This one is the biggest, most common side effects we see when it comes to medications and teeth. If you start paying attention to the drug commercials on TV every night, you’ll notice them mention “dry mouth” as one of the side effects. That’s because so many medications—both over the counter and prescription alike—also decrease saliva flow.

That being said, some types of medications are “worse” when it comes to causing xerostomia than others. Such as:

Go and rifle through your medicine cabinet, and chances are that 90% or more of the medication that’s in there will have dry mouth listed as a common side effect.

Dry mouth significantly raises your chances of getting cavities, which is why xerostomia-causing medications and teeth need to be monitored carefully. Not to mention that a dry mouth can also contribute to bad breath.

To reduce your risk for dry mouth :

The key is to keep your mouth moist, to limit bacterial buildup. Sipping on water frequently throughout the day may not be great for your bladder, but it’s super helpful for your mouth.  

3) Medicine That Causes Burning Mouth

Have you ever felt like your mouth was just completely on fire? Burning mouth syndrome is attributed to a number of situations (including reflux disease) but it’s also linked with medications that people take for high blood pressure.

Burning mouth syndrome can make it difficult to eat certain types of foods or textures. Your favorite spicy foods may be entirely off-limits.

On the other hand, medications such as antidepressants or anticonvulsants can actually help with symptoms of burning mouth.

There are some other factors you’ll want to rule out before casting the blame on your medication, however. Burning mouth syndrome can be caused by things like certain autoimmune disorders, Parkinson’s disease, or even a hormonal imbalance.[2] Allergies and certain vitamin deficiencies (vitamin B, zinc, and iron) may also be to blame. You’ll want to work extremely close with your doctor and dentist to rule out all of the commonly known risk factors to find the fastest path to relief.

Radiation therapy is another common cause of burning mouth syndrome. Since it’s frequently combined with chemotherapy drugs—which can irritate the inside of your mouth—cancer patients may have an especially hard time with irritation inside of their mouths.  

4) Fungal Infections Caused By Medication

Oral side effects of medications can sometimes involve an unbalanced number of good and bad bacteria. Antibiotics are a classic example. When you take antibiotics, they kill all types of bacteria, including the good ones. Our bodies need healthy bacteria to aid in things like digestion (which starts in our mouth.) That’s why so many people recommend taking probiotics or eating foods like yogurt if you’re on an antibiotic.

But let’s say for a minute that you’re on an antibiotic and your normal oral flora is starting to become unbalanced. Now, the bacteria that normally aren’t there may start to take over. It’s a classic recipe for fungal (yeast) infections like “thrush”.

Corticosteroids can do the same thing. Like the medications people take for Lupus, arthritis, or IBD. Especially if you’re using them for an extended period of time.

Yeast infections can occur in numerous parts of the body, and the mouth is just one of them. So, if you’ve been on an antibiotic or corticosteroid regimen for an extended period of time, you’re at a fairly high risk of getting an oral fungal infection. It’s not out of the ordinary to have to take an anti-fungal medicine to counteract a yeast infection from another prescription you already took.

Denture wearers, take note. Make sure you’re cleaning both your prosthesis and the inside of your mouth thoroughly each day. Do not sleep in your denture, no matter how tempting it may be. If you do, you’re at a much higher risk of developing a yeast infection.

5) Medicine That Causes Gum Swelling (Gingival Overgrowth)

Did you know that certain types of medication can cause your gingiva (gums) to grow? Overgrow, in fact. We call this condition “gingival hyperplasia”.

Gingival hyperplasia is where your gums begin to grow, spread, and expand. They tend to look bulbous and lumpy along the gumlines. Obviously, this scenario can cause some major cosmetic concerns, but it also isn’t very healthy because food and plaque can get stuck around it. Cleaning your mouth can be especially challenging.

Some of the most common medications to cause gum swelling/overgrowth are the ones that people take for high blood pressure or to control seizures. Calcium channel blockers, in particular, are most known for causing gum overgrowth.

If you’re someone who wears a denture, you might actually need to have some of these tissues reduced or removed. Otherwise, it could be impossible for your prosthesis to fit in your mouth!

You’re probably wondering how dentists treat gingival hyperplasia. There are two options: “wait and see” or having it physically removed. Your dentist or a specialist can use a laser to trim away the excess tissue with little to no bleeding. Otherwise, a more conventional surgery might be required.

6) When Medicine Causes Taste Changes

Certain medications can cause a temporary metallic taste to develop inside of your mouth. Usually, they’re antibiotics. Let’s say you’re super stuffy and your physician writes you a prescription to clear up a sinus infection, then you start to get your smell back but everything tastes like metal…that’s probably what it is.

Blood pressure medication can also cause a metal taste in your mouth, as well as one that’s sour or bitter. For people who are already altering their diet because of cardiovascular disease, this can be especially frustrating!

Other meds such as those taken for your thyroid, neurological reasons, or psychotropics can also alter the taste inside of your mouth.

The good news is that the majority of medication-induced taste changes are temporary. Not all of them are, but most are short-lived.

7) Tooth Discoloration And Staining

Some types of medications can cause intrinsic (internal) or extrinsic (external) tooth stain. Intrinsic stains are those that form while the tooth is developing, which means the medication would have been taken in early childhood or even by your mother before you were born. Tetracycline is a classic example. This antibiotic is no longer prescribed for young children or if you suspect that you’re pregnant, as it can affect the fetus.[3] The permanent staining is so severe that extensive cosmetic treatment is usually required to get rid of it.

And then there are the external stains. These are the ones that your hygienist can usually polish off when you go in for a dental cleaning. While we typically attribute extrinsic stains to things like coffee or tobacco use, medicine such as antihistamines or prescription mouthwashes may also be responsible.[4] Yes, I said mouthwash. Particularly chlorhexidine, which is usually prescribed if you have moderate to advanced gum disease; it should only be used for 10-14 days at most, simply because of the stain it tends to cause.

8) Black Hairy Tongue

Trust me, you don’t want to Google the pictures. Black hairy tongue and white hairy tongue are basically exactly what they sound like they are. The tiny little papilla on the surface of your tongue becomes elongated and looks like hairs. And depending on what medication you’re taking, if there’s an infection, or which lifestyle habits you stick to, those papilla can take on a white or black color.[5] Hence terms like “black hairy tongue.”

Now, usually, something like black hairy tongue is caused by smoking, poor oral hygiene, rinsing with peroxide, or dry mouth. But some medications can also raise your risk of it as well. For some people, antibiotics, NSAIDs, and even radiation treatment can cause black hairy tongue to develop.

9) Medicine Cause Mouth Sores (Ulcers)

Sometimes it’s necessary to take medications that are also extremely tough on our body overall. In this case, I’m talking about chemotherapy drugs used for cancer treatment. These common chemo meds can cause the inside of your mouth to feel raw or even develop sores/ulcers/canker sores. But there really isn’t a way around them.

Even if you’re not fighting cancer, medications like aspirin, sulfonamides, or penicillin can set you up for mouth sores.  Some people even claim that other antibiotics or anti-seizure meds cause problems.

If you know that a certain type of medicine is “harder” on your body than others, be sure to communicate your concerns with your physician, specialist, and dentist.

Sometimes it’s possible to experience an inflammation of the lining of your mouth, instead of localized sores. We call this condition “mucositis” because it’s an inflammation of the mucosa. Like ulcers or mouth sores, mucositis can also be triggered by a lot of the same medications.

“Should I Stop Taking My Medication?”

Never discontinue your medication without talking to your doctor. Especially if it’s for something important. You and your doctor can work together to weigh the pros and cons of the oral side effects of medications (feel free to get your dentist's input) and determine if other options are available.

Sometimes different types of medications or forms of medicine may work better. For instance, if you have a child that needs to take a prescription by mouth and they usually get it in a syrup form, now would be a good time to try to teach them how to swallow a pill. Small changes can make a big impact when it comes to medications and teeth.

Overcoming Oral Side Effects From Medication 

Oral side effects of medications are more common than you think. From raising your risk of cavities and tooth stain to permanent discoloration and dry mouth, almost every medicine impacts your mouth—or the rest of your body—in some way.

Sometimes there are things you can do to counteract the side effects of medicines that you’re taking. Such as:

The Next Time You’re At The Dentist

When you plan a dental checkup, giving your dentist a list of medications that you take each day is probably the last thing on your mind. You might even wonder why they want such detailed medical history for something as simple as a teeth cleaning.

But now that you know medications that cause tooth decay or dry mouth are fairly common, you’ll be more inclined to want to partner with your dental team on a holistic level. The better you communicate with your dentist and hygienist, the more likely you will be able to minimize the oral side effects of medications that you’re taking.