Doctor David Kessler, who ran the FDA from 1990 to 1997, doesn't hold back when talking about the explosion in opioid use in the last two decades.

"This has been one of the great mistakes of modern medicine," said Kessler, who went on to say opioid addiction in the U.S. amounts to an epidemic.

Dr. David Kessler CBS News

"FDA has responsibility, the pharmaceutical companies have responsibility, physicians have responsibility. We didn't see these drugs for what they truly are," Dr. Kessler said.

From 1999 to 2014, sales of opioids quadrupled in the U.S. -- and so did the number of opioid-related overdose deaths, reports CBS News' Jim Axelrod.

"There was a notion that pain was the fifth vital sign, you wanted to relieve pain, that that was essential. You dosed until the pain was alleviated," Kessler explained.

That, said Kessler, was a costly mistake. Seventy-eight people now die each day from overdosing on painkillers. But the CDC didn't issue prescription guidelines until this past March. They recommended doctors try over-the-counter pain medications before prescribing more limited quantities of opioids -- but did not mandate they do so.

But are the guidelines strong enough? "We'll see," said Kessler. "This is an American condition. This is an American disease."

In the 21 years since OxyContin first came on the market, it has generated more than $35 billion in sales.

"The inappropriate promotion of drugs contributed significantly to this epidemic," Kessler said. "Because drug companies took a small piece, a sliver of science and widely promoted it as not being addictive. That was false."

While pill mills are among the most visible signs of the epidemic, Kessler said two-thirds of painkiller prescriptions are written by well-intentioned physicians trying to do right by their patients.

"Everybody has to do better. The CDC guidelines need to be implemented. Pharmaceutical companies need not over-promote. Doctors need to prescribe more wisely in a more limited way."

"But it's going to take a societal shift, it's bigger than any one of those steps, in order to change this epidemic."

When asked about his responsibility as the head of the FDA, he said the epidemic took hold after he left the agency in 1997, but does admit he should have pushed for stricter prescription practices when he was still in charge.