Hamilton paramedics rushed three people to hospital for "suspected" fentanyl overdoses this weekend.

EMS Superintendent Angela Schotsman told CBC News that two people overdosed last night, and another person overdosed on Sunday morning.

The powerful opioid painkiller is suspected as the cause in those cases, she said, but "it's difficult to say [for sure] if they were fentanyl, because we don't know the exact cause."

To be certain, the drugs the person took would need to be tested, or a toxicology report would be needed in the case of a person who overdosed and died.

Schotsman couldn't immediately say if the three overdose cases resulted in any deaths.

According to the city, Hamilton Paramedic Services responded to 25 calls related to opioid overdoses between Jan. 10 and Feb. 18 this year.

Former opioid addict Nicole and Debbie Bang, the manager of St. Joseph’s Healthcare Womankind addiction service, explain prescription painkiller addiction. 3:57

There have been more opioid-related deaths in the Hamilton LHIN over a five-year period than anywhere else in the province, according to a recent study from the Institute for Clinical Evaluative Sciences.

The report also shows that the Hamilton LHIN (which includes Niagara, Haldimand and Brant) had the highest number of opioid-related hospital admissions and emergency department visits in the entire province in 2014.

According to preliminary reports from the provincial coroner's office, there were 47 deaths in Hamilton caused by opioids or a combination of opioids and alcohol in 2015.

The city says that in November of last year, there were 36 emergency department visits for opioid poisoning at Hamilton hospitals.

That's the highest number of visits in the last 19 months of available data.