Waterloo Region is seeing a sharp increase in opioid-related emergencies, with paramedics responding to nearly twice as many calls in the first half of 2026 compared to the same period last year. According to Region of Waterloo Public Health, paramedics responded to 825 opioid-related calls between January and June 2026, up from 438 calls during the first six months of 2025. Health officials said while it’s difficult to identify one specific cause for the increase, changes in the illicit drug supply are making it more dangerous. “While it’s not usually possible to pinpoint the exact reasons behind the increase in overdoses, we do know that changes in the toxicity of drug supply can lead to increased risk for users,” said Katie McDonald, the Region’s manager of health system integration. Sanguen Health Centre operates a drug-checking program in Waterloo Region. Testing has revealed fentanyl is increasingly being mixed with unexpected substances. “We are seeing an increase in medetomidine, which is a veterinary tranquilizer. That’s very concerning, and it is really making the current supply even more toxic and more risky,” said Julie Kalbfleisch, Sanguen’s director of fundraising and communications. Medetomidine can cause heavy sedation, slow breathing and lower blood pressure. Unlike opioids, its effects are not reversed by naloxone. “Still give them naloxone because there could be other things in the supply, like opioids, which would help reduce the reactions,” Kalbfleisch said. Public health data shows Kitchener continues to record the highest rate of opioid-related paramedic calls in the region. But there are encouraging signs. “The suspected drug-related deaths are not increasing in the same way that paramedic service calls are,” McDonald said. Public health officials believe wider access to naloxone may be helping prevent fatal overdoses. Although the closure of Kitchener’s Consumption and Treatment Services (CTS) site reduced local harm reduction services, Sanguen recently secured funding to continue operating its drug-checking equipment. The organization also received an exemption allowing the technology to be used through its mobile outreach unit. Advocates said the crisis extends beyond the increasingly toxic drug supply. “We have this convergence of the toxic drug crisis, along with the affordability and housing crisis,” Kalbfleisch said, adding that people are hesitant to go through recovery programs if they’re just going to end up on the street at the end of it and get stuck in that cycle. She added the public health figures likely underestimate the scope of the crisis because they only include incidents attended by paramedics. Many overdoses are reversed by family members, friends and frontline agency staff without emergency services ever being called, meaning the true number of overdoses occurring in the community is likely much higher than official data suggests.