PHOENIX (3TV/CBS 5)-- You have heard it before, "We are in the middle of a public health crisis."
Fentanyl is wreaking havoc across the nation and in Arizona. It is not a new drug as it was created in the 1960s.
Since then, it has been used in the medical community as a pain reliever.
Dr. Natalie Strand is a pain management expert at the Mayo Clinic in north Phoenix. She wants people to understand that opioids are useful in the right scenarios.
"If its prescribed in a controlled setting for the right diagnosis, it can be safe and it can be effective," Strand said.
Strand added that fentanyl also helps with acute pain and it is used in certain surgeries and to treat cancer pain.
"It's also useful because it comes in the patch form," she said. "That's more in the chronic pain setting, if they have a problem ingesting medicine."
Fentanyl is also good in the way it works especially for patients with kidney disease.
"Fentanyl is one of the few medications, it doesn't metabolize," Strand added. "What that means is it's clean. doesn't build up in your system if you have kidneys that don't excrete well."
Strand added that in the pain management community, fentanyl does have some important uses and in some cases, it's actually safer than other drugs.
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The bad? Fentanyl is now the opioid of choice on the streets. Medical grade fentanyl is very different from what is found on the streets.
As a prescription, fentanyl usually comes in a liquid form given as a shot or nasal spray. It also comes in a patch.
"On the street, it comes in a pill or a powder and it is very, very potent. And that's what make it so dangerous and so deadly," said Strand.
"The ugly part of street fentanyl is that its very easy to overdose, it's much more potent than any form you can get through a pharmacy or a prescription."
So where is street fentanyl coming from?
Drug traffickers are bringing the opioid into Arizona. Just last month, border patrol agents in Nogales had their biggest fentanyl bust.
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Border agents found more than 250 pounds of the drug, mostly in a powder form hidden in a Mexican produce truck. The drug's street value is about $3.5 million dollars.
"Street fentanyl can kill you the first time you try it," said Strand.
"It's not something to experiment with. Its very addictive, it's very potent and you can die the first time you use it."