Montreal Public Health warns of rise in overdose deaths linked to carfentanil

Montreal Public Health has issued an alert over a sustained increase in overdoses and several deaths linked to carfentanil, a synthetic opioid far more potent than fentanyl. Officials said nonfatal overdoses have stayed unusually high since March, and ambulance crews have already used naloxone as many times in the first half of 2026 as they did in all of last year. Public health said carfentanil has been confirmed in eight suspected overdose deaths since an alert was first issued in April, though the final total could rise as toxicology testing continues. Health officials said the drug is being found in substances sold as fentanyl, sometimes mixed with other fentanyl analogues and sedatives. They urged anyone who sees signs of overdose to call 911, give naloxone if available, and stay with the person until help arrives. Officials said hot weather and a more toxic drug supply may be contributing to the trend, especially among people experiencing homelessness.