Beyond Ozempic breath: A U of T Dentistry researcher examines GLP-1s and oral health

By Diane Peters

At his practice in North York, U of T Dentistry associate professor Aviv Ouanounou often treats patients with complex health conditions such as diabetes, cardiovascular disease and obesity. Increasingly, many of these patients are trying glucagon-like peptide-1 agonists, or GLP-1 drugs, which go by names such as Ozempic and Rybelsus. 

He’s been trying to figure out how these popular medications impact oral health. With about three million Canadians taking GLP-1 drugs, according to a 2026 survey by Leger, many other dentists and their patients have questions, too.

“We are increasingly seeing these patients,” says Ouanounou. “We need to know what these medications are doing. There’s very little research on their oral health implications. There’s been a lot of attention on their metabolic effects and cardiovascular benefits but not much on oral health.”

As a researcher who specializes in pharmacology, Ouanounou has taken on the task of explaining the mechanism of action of GLP-1s, reviewing the literature — which is made up of mostly case reports — and offering guidance to dentists in his study “Oral Health Considerations and Dental Management Guidelines for Semaglutide Medications.” 

Published in the Canadian Journal of Diabetes, it is one of the first studies to take a big-picture view of GLP-1s and oral health, and suggest basic guidance for oral health professionals.

“I believe we are one of the pioneers,” says Ouanounou, who worked with second-year DDS student Karina Kofman.

They found that GLP-1s offer a mixed bag for dental health. Better managed or even reversed metabolic and inflammation-related conditions offer a big positive for the health of teeth and gums. Uncontrolled diabetes, in particular, has serious oral health implications. “Diabetic patients are slow to heal, they have more dry socket and more infection. But when they’re under control because of this medication, there’s less dry socket, and the wound healing and infections are better.”

However, these medications also have side effects that can trigger dental concerns. “Many of the oral health implications are indirect. These drugs do not directly damage oral tissue,” says Ouanounou.

For starters, like many medications, they can cause xerostomia (dry mouth). 

“Saliva plays an important role in protecting the teeth, in buffering acids, in controlling bacterial growth. When saliva flow is low, patients become more vulnerable to cavities, to oral infection,” he says. They can be more prone to yeast infections, too.

The paper suggests oral health professionals monitor patients for dry mouth, increase the frequency of cleanings — to as often as every three months — and encourage them to double down on brushing and flossing. They can also use sugar-free gums or lozenges containing xylitol and try gustatory stimulants to aid saliva flow; patients with severe cases may need a prescription for systemic agents such as agonist pilocarpine.

So-called Ozempic breath and Ozempic burp, meanwhile, may be the result of slowly digesting food in the mouth or stomach emitting an odour — plus a dry mouth may lead to more food particles sticking around. These drugs can also cause reflux and belching that smells of sulphur. Getting regular cleanings, staying hydrated, increasing oral hygiene routines and opting for antibacterial and zinc-containing toothpastes can help.

As well, GLP-1s can trigger vomiting, which exposes the teeth to acid. Patients dealing with this should rinse their mouths right after, and delay brushing their teeth for at least 30 minutes, doing so with a gentle brush and fluoride.

They may also need their prescription altered or even stopped before undergoing oral surgery.

Since GLP-1s are so new, there are no consensus guidelines published by oral health organizations. Ouanounou hope this study will get such a process started. “This is intended to serve as a foundation.”

However, he says we need prospective studies, including large ones and those with control subjects. “We need to be evidence-based,” he says.

For his part, he would like to do a trial of patients taking GLP-1s and look at caries risk and also salivary flow and its oral health outcomes.

Currently, there is sufficient evidence to show that these drugs cause ripple effects on teeth and gums — but oral health professionals and patients can manage them. Dry mouth and Ozempic breath aren’t ideal, but they shouldn’t prevent people from taking these game-changing medications and getting many aspects of their whole-body health under control.

“I always teach my students that in pharmacology, it’s about your judgement around whether something is benefiting the patient or not,” says Ouanounou. “It’s about risk and reward.”

Top photo: Pevel Danilyuk (Pexels)