oxycodone opioid
Opioid pain pill Oxycodone, prescribed for a patient with chronic pain, on display in Norwich, Connecticut, March 23, 2016. John Moore/Getty Images

A Pennsylvania doctor was charged Thursday after his prescription of nearly 3 million doses of opioids during a recent 19-month period caused the overdose deaths of six people. According to the U.S. attorney's office in Harrisburg, Dr. Raymond Kraynak, 60, of Mount Carmel, was indicted on five counts of drug delivery resulting in death, 12 counts of unlawful distribution of a controlled substance and two counts of using his doctor's offices as "drug-involved premises."

Attorney David Freed said in a news release that Kraynak prescribed approximately 2.7 million units of ocycodone, hydrocodone, oxycontin, and fentanyl to almost 3,000 patients between January 2016 and July 31, 2017, making him the state's largest single prescriber of those drugs.

Kraynak operated two offices in Mount Caramel and Shamokin known as Keystone Medicine Associates. Federal prosecutors were seeking forfeiture of Kraynak's medical offices, his Pennsylvania medical license, and $500,000.

The names of the patients, who died between 2013 and 2015, were not revealed.

Kraynak, who was arrested Thursday, said he hoped to be released on bail so he can help his patients obtain treatment.

"At this point, we haven't received any discovery, so I really don't know exactly what's going on here," his defense lawyer, Tom Thornton said, according to the Associated Press. "Our greatest concern is for Dr. Kraynak's patients who still need treatment, they need care."

Patients under Kraynak's treatment accused him of issuing prescriptions without conducting proper medical exams, verifying his patients' medical problems or assessing their risk of drug abuse.

"There's a human cost to this and there are people out there who have been prescribed hundreds and hundreds of pills over time," Freed said at the news conference to announce the charges, adding that it was concerning that the allegations came forward amid the national opioid crisis.

Freed called the volume of pills Kraynak was alleged to have prescribed, "staggering."

"Nobody can deny that the crisis is in the public domain, and physicians certainly know that," Freed said.

If convicted, Kraynak could face a mandatory minimum sentence of 20 years.

Opioid addiction and abuse is one of the biggest health issues facing the U.S., with many health officials and advocates referring to the situation as an “opioid crisis” or the “opioid epidemic.”

People who are overdosing on an opioid will be unconscious, have depressed breathing and have pinpoint pupils, according to the World Health Organization. The U.S. Substance Abuse and Mental Health Services Administration warns to call 911 if the victim is pale, clammy and limp; has purple or blue fingernails and lips, and is vomiting or making gurgling sounds.

In October, President Donald Trump declared opioid epidemic as a public health emergency.

"We can be the generation that ends the opioid epidemic,” he said. "This epidemic is a national health emergency. Nobody has seen anything like what is going on now. As Americans, we cannot allow this to continue. It is time to liberate our communities from this scourge of drug addiction. Never been this way. We can be the generation that ends the opioid epidemic. We can do it."