 A Jacksonville Fire and Rescue Department transport unit is often the next step for somebody who's overdosed. They're going to become extremely cyanotic due to the lack of breathing. They're going to be blue, unresponsive completely. Jacksonville Rescue Division Chief David Castleman says first responders have been getting more calls about heroin. Really in January we noticed that there was a marked increase in our responses to not only overdoses but specifically heroin overdoses. When paramedics respond to overdoses, they'll administer Narcan, a drug that reverses an overdose within minutes. Jacksonville's Fire and Rescue Department has used a lot of it this year. From 2011 to 2015, we averaged between two and three hundred administrations a year. In the last year alone, we've seen a 100% increase in the amount of Narcan that's been administered for these overdoses. But more importantly, since January, up till now in just this last four months, we have had a 278% increase in Narcan administration for overdoses. Before last month, Narcan was only available on 41 rescue vehicles. Now all the advanced life support engines carry it too. He says he'd like to expand that to every engine in the department. Heroin use is sweeping the streets of Jacksonville. That as the Chief tells WJCT and most of the fatal cases, heroin isn't the primary killer. What's interesting about fentanyl is that it's 60 times more potent than heroin. That's a synthetic analgesic and these drug users, or I should say drug manufacturers and dealers, they're cutting synthetic fentanyl with heroin. And so it gives us cheaper to manufacture and it's much quicker to produce than heroin. In hospitals, fentanyls use for anesthesia, epidurals and chronic pain like for people who have cancer. Castleman says in Jacksonville, it's what's killing heroin users most often. The medical examiner's office contacted his department to let them know most deaths by heroin overdose were actually deaths by fentanyl. We've had numerous cases that we responded to where the individual was using drugs alone and we found them dead with the needle still in their arm. That's how quickly that that drug acts. He says most drug users don't know what they're getting isn't pure. And so I think the message is while we're not condoning drug use is that if you are an addict and you are using illegal drugs, you should never use drugs alone. For Community Thread, I'm Lindsay Kilbride.