Police in Saint John are warning the public to watch their drinks after two cases of possible tampering.

The Saint John Police Force say an unidentified substance might have been added to a person’s drink in two recent cases.

The warning comes as students prepare to head to university.

“Once Frosh Week starts after Labour Day, then the first couple of weeks you’ll see a lot of new faces that are new to the Saint John area or new to being 19,” says bar owner Corey McGill. “We want them to have fun and have a great time for the next couple of years while they’re in schools, but remember, be safe.”

Police say it isn’t known whether the substance was added in the form of a liquid or powder. They say the substance can be odourless and undetectable and common side effects can include nausea, dizziness, amnesia and, in some cases, death.

They also say the behavior exhibited quite often leads one to believe the person is suffering from an over consumption of alcohol.

Police and bar owners are warning patrons not to leave food or drinks unattended or accept beverages that could have been tampered with.