Two cities on two different sides of Boston saw a massive spike in overdoses and Narcan usage over the past week, investigators said. 

Brockton saw 45 heroin overdoses between Jan. 13 and Jan. 17, The Brockton Enterprise reported. 

On average, Brockton sees about three overdoses per day, police said. None of the overdoses in last week’s uptick were fatal, according to Mayor Bill Carpenter’s official Facebook page, and many people were revived via Narcan.

“Our first responders are doing incredible work, no deaths during these past [four] days,” Carpenter wrote on the public page. “We must and will do more to help people who are struggling with addiction. Soon, we will roll out the Champion Plan, a Gloucester-type model, that will assist those ready to seek treatment for their substance abuse disorder.” 

Brockton city officials plan to roll out the Champion Plan, which Carpenter said will help treat, not arrest, people who are using opioids. It will run on the strength of volunteers, called “angels,” to come to the aid of those struggling with addiction.

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But Gloucester saw four overdoses in a 24-hour span, according to Police Chief Leonard Campanello. 

“Some will say ‘oh it’s a bad batch,’” Campanello wrote on the department’s Facebook page on Monday morning. “Bullsh--... there is no good Heroin. You are important and worth it. There is no incentive or punishment that this disease responds to.”

Again, the use of Narcan revived those who were overdosing.

“Gloucester had 4 overdoses in the last 24 hours,” Campanello wrote on the department’s Facebook page on Monday morning. “That’s the bad news. The good news is all were brought back to us by the increased availability and proliferation of Narcan.”

Officials are warning people that fentanyl is becoming more prevalent in heroin. Dr. Dan Carr, Professor of Public Health and Community Medicine Program Director, Pain, Research Education & Policy at Tufts Medical Center told Metro in August that the synthetic opioid is roughly 50 times more powerful than regular heroin. 

“It augments all of the risks that already exist in an opioid,” Carr said. “Unlike morphine, fentanyl can cause muscles to go so rigid, they can’t breath even if they want to”.

According to DrugAbuse.org, mixing fentanyl with street-sold heroin or cocaine markedly amplifies their potency and potential dangers. According to their data, Narcan is one of the best ways to prevent an overdose if a responder can administer it in time.