Montreal public health is warning of an alarming increase in drug overdoses in recent weeks, tied to the presence of fentanyl mixtures.
Since the end of March, health authorities say they have recorded a significant rise in the number of non-fatal overdoses in the city. Frontline workers say they have also seen the increase.
“We consulted our staff when we received this notice, and indeed we have seen a tick up. We see about five overdoses a week,” said James Hughes, president and CEO of the Old Brewery Mission.
Workers say rises in overdoses among opioid users are not unusual, but what is different now is the growing presence of carfentanil mixed with fentanyl.
Carfentanil is about 100 times more potent.
“Very dangerous and we’re really very nervous about it. Luckily the naloxone intervention does work,” Hughes said. Naloxone is a medication used to reverse the effects of an opioid overdose.
Urgences Santé is also reporting an increase, based on the number of times crews have administered naloxone.
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“We did see an increase since the 10th of April of close to more than 60 cases. To be specific, about 67 have been reported by our crews,” said Alexandre Sapone, chief of operations. That number was recorded in less than two weeks.
According to Montreal public health data, paramedics were administering naloxone about 75 times per month in 2025.
Urgences Santé cautions there could be more cases that are not logged if naloxone is administered by someone else. Officials also say it can be difficult to determine what substance was taken.
“It’s hard to say what the substance is. Sometimes we can refer to carfentanil, or fentanyl. Sometimes it can be rainbow fentanyl, blue rock, pink fentanyl,” Sapone said.
Montreal public health says carfentanil had previously only been detected occasionally, and believes the current increase marks a significant change in the street drug market.
The trend is raising concerns among those working with unhoused people, who they say are often targeted by drug dealers.
“In the last year we have seen continual gradual increase in overdoses that we are intervening in,” said David Chapman, executive director of Resilience Montreal.
Intervention workers say they are bracing for more deaths, particularly among those using drugs alone or in isolated spaces.
“And if they’re using in spaces alone and hidden spaces, the probability is not good,” Chapman said.
They say they hope law enforcement can address the root of the problem before the situation worsens.