Are You Taking a Weight Loss Injection?
Here's What It Could Mean for Your Teeth
If you're taking Wegovy, Ozempic, Mounjaro, or another GLP-1 weight loss or diabetes medication, you're in good company. Millions of people around the world are on these medications - and they're genuinely life-changing for many. Weight loss, better blood sugar control, improved heart health. The benefits are real.
But there's something your dentist needs to know about. And honestly, something you need to know too.
These medications can affect your mouth - and not in ways that are obvious until real damage has already been done.
Why weight loss medication could be a dental concern
GLP-1 medications work throughout the body, including in your salivary glands. Recent research suggests that semaglutide (the active ingredient in Wegovy and Ozempic) may interfere with normal saliva production at a biological level - not just as a coincidental side effect, but as a direct result of how the drug interacts with receptors in gland tissue.
Why does that matter? Saliva is your mouth's best defence. It neutralises acids, washes away food, helps repair early damage to tooth enamel, and protects the soft tissues in your mouth. Without enough of it, your teeth become far more vulnerable.
Dry mouth - the clinical term is xerostomia - is uncomfortable on its own. But it also means that any acid challenge your teeth face does significantly more damage than it otherwise would.
The risks don't stop at dry mouth
Several things tend to happen in the early months on a GLP-1 medication that, together, create a real window of risk for your teeth:
You may be drinking less without realising it. These medications suppress appetite - and that often means people forget to drink as well as eat. Missing the fluids you'd normally have with meals adds up. Dehydration makes dry mouth worse and concentrates acids in your mouth.
Nausea and vomiting are common at first. Most people experience some degree of nausea when starting or increasing the dose. If vomiting occurs - even occasionally - gastric acid reaches your teeth directly. The most characteristic sign of this kind of damage is wear on the inner surfaces of your upper front teeth and the chewing surfaces of your back teeth. It often goes unnoticed until it's significant.
Your taste preferences may change. Altered taste is a known side effect. Some people find themselves gravitating toward more acidic or sweet foods and drinks to compensate when things taste different. This can increase acid exposure from the diet at exactly the time when your mouth's defences are already lowered.
Add all of this together - less saliva, less fluid, possible vomiting, and changed dietary habits - and the early months of treatment can be a particularly vulnerable time for your teeth.
But there's genuinely good news too
Here's the part that doesn't get talked about as often: GLP-1 medications may actually improve one of the most common hidden causes of tooth wear.
Excess weight - particularly around the abdomen - increases pressure on the stomach, which pushes acid upward into the oesophagus and throat. This is gastro-oesophageal reflux disease (GORD), and a related condition called laryngopharyngeal reflux (LPR), where acid reaches even higher - silently damaging teeth while you sleep, often with no obvious heartburn symptoms at all.
Sustained weight loss reduces that pressure. For many patients, losing weight meaningfully reduces or even resolves their reflux. If acid reflux has been quietly damaging your teeth, your oral environment may genuinely improve as you lose weight on these medications.
The picture is nuanced. For some patients, GLP-1 medications may reduce their tooth wear risk overall. For others - particularly those without significant reflux - the dry mouth and early side effects create net vulnerability. Your dentist can help you understand where you sit.
What to tell your dentist - and what to ask
Please mention your GLP-1 medication at your next dental visit, even if it doesn't feel relevant. Many patients don't connect their weight loss injection to their oral health - but your dentist needs this information to look after you properly.
It's also worth knowing that many people don't connect their reflux symptoms to their teeth either. Symptoms like a chronic cough, a feeling of something stuck in the throat, hoarseness, or post-nasal drip can all be signs of acid reaching the throat - and they're easy to overlook or attribute to something else. If any of those sound familiar, mention them too.
What your dentist may do:
Ask about dry mouth and check your saliva flow
Look carefully for early signs of erosion - particularly on the inner surfaces of your teeth
Ask whether your reflux symptoms have changed since starting treatment
Talk through ways to protect your teeth during the higher-risk early months
Simple things you can do at home:
Drink water consistently throughout the day - don't wait until you're thirsty
Use a fluoride toothpaste, and consider a remineralising toothpaste if dry mouth is ongoing
Avoid brushing immediately after vomiting - rinse with water first and wait at least 30 minutes
If reflux is a concern, sleeping with your head slightly elevated can help reduce overnight acid exposure
Don't sip on acidic drinks (juice, sparkling water, kombucha, soft drink) throughout the day
One more important note if you need dental sedation
GLP-1 medications significantly slow down how quickly your stomach empties. This matters if you're having a dental procedure under intravenous sedation or general anaesthesia. Standard fasting times before a procedure may not be long enough to ensure your stomach is empty - which creates a safety risk.
If you're on one of these medications and have any dental procedure involving sedation coming up, tell your dentist and anaesthetist in advance. This is important, and the guidance around it has recently been updated in Australia and New Zealand.
The bottom line
GLP-1 medications are genuinely changing lives. But like any powerful medication, they interact with your whole body - including your mouth. The dental profession is only beginning to understand the full picture, and the evidence is still developing.
What's clear right now is that awareness matters. Knowing you're on this medication, checking in with your dentist, and taking some simple protective steps can make a real difference to your long-term dental health - while you enjoy the broader benefits these medications offer.
Your teeth can last a lifetime. Let's make sure they do.
Dr Andrea Shepperson is a restorative dentist based in Auckland CBD, with a practice dedicated to the diagnosis and treatment of tooth wear. She sees patients from across New Zealand and internationally.