MIAMI - Prescription drug abuse is a growing problem in this country. CBS News chief investigative correspondent Armen Keteyian found a big part of the problem are rogue pharmacies distributing millions of pills.
At age 23, Heather Belleme had a dark secret. For two years, she was addicted to the powerful pain-killer oxycodone.
"I would never think in a million years Heather would abuse drugs, never," says her mother Lisa.
Even though Belleme didn't have a need for oxycodone, she had no problem getting prescriptions from doctors - and getting them filled.
In March, she walked into a Fort Lauderdale pharmacy with a prescription and walked out with 168 pills of oxycodone by paying $700 cash. Four days later she died of an overdose.
"She was just so full of life," Lisa says. "And, it was taken away."(Scroll down to watch the video)
Oxycodone is now the most abused narcotic in the country. In 2010 alone, pharmacies in this country ordered more than 3.1 billion doses of oxycodone.
Pharmacies in Florida purchased more than 421 million of those doses - more than 23 states combined.
Mark Trouville is in charge of the U.S. Drug Enforcement Administration's Florida field office. Its new focus is rogue pharmacies.
"When we talk about pharmacists that are doing the wrong thing," Trouville says, "we're talking about a pattern of consistent abuse that is absolutely motivated by greed, and not by the good."
Rogue pharmacies work with shady doctors to illegally dispense millions of pills to addicts and drug dealers.
"They're nothing but moneymaking operations," Trouville says.
"Organized drug dealing?" Keteyian asks.
"It's organized drug dealing, it absolutely is."
"How difficult is it to identify, and then target and bust these pharmacies?"
"We have to go beyond - we have to show there clearly is an intent to violate the law. So it's not easy."
According to DEA records, one obscure, strip-mall pharmacy in Pembroke Pines, Fla., purchased more oxycodone than any retail pharmacy in the nation in 2009. And, it was No. 1 in Florida last year -- purchasing more 2.3 million doses. That's 40-50 times more than pharmacies in the same neighborhood.
Keteyian went to Pembroke Pines to ask the owner, pharmacist Stephen Schwartz about the large numbers of doses. But, Schwartz only wanted to talk about the oxycodone prescriptions that he's filling now.
"Now we only get, we fill about five scripts a week," Schwartz says.
"Is that it?" Keteyian asks. "Because in 2010 you did 2.3 million. Ah, 50 times. Here's the numbers right here."
"I am not doubting, but I, could you please leave the store. I really have no comment."
"Any explanation at all?"
"Because we filled a lot doesn't mean we didn't do our due diligence."
Schwartz says he violated no laws -- and the pharmacy has not been charged with any crime.
"When you see those kinds of numbers," Keteyian asks, "2.3 million purchased, red flags are raised?"
"Yeah, in a general sense, that's the smoke where there's fire," Trouville replies.
"The pharmacist has a legal and ethical responsibility to make sure they don't dispense drugs that are going to be abused or diverted," says Carmen Catizone, Executive Director of the National Association of Boards of Pharmacy. He says pharmacists are required by law to watch for suspicious prescriptions.
The pharmacist who filled Heather Belleme's last prescription told CBS News that he verified it was genuine. How she got it, or what she did with the pills is not his responsibility.
Belleme's grieving mother won't accept those words. She wanted to tell her story to us so that no one will forget how her daughter died.
"I will never be whole again. Never. I am broken," Lisa says. "I can't bring Heather back but I can save other people."
The Florida legislature recently passed tougher laws on who can dispense oxy. Still, the DEA says applications to open up new pharmacies in the state have skyrocketed - accounting for half of all new applications nationwide.