DENVER (CBS4)– The U.S. Attorney for Colorado has called the abuse of prescription drugs an “epidemic.”

Two doctors in the Denver metro area are facing criminal consequences but there are estimated to be many more who haven’t been caught yet.

Dr. Kevin Clemmer has already pleaded guilty.

He worked at an office building near 44th and Wadsworth in Wheat Ridge.

Clemmer over-prescribed oxycodone dozens of times. At least one case led to a deadly overdose, Ryan Lujan, who was found dead in 2010 as a result of oxycodone use. The prescription was written by Clemmer.

Prosecutors claim Clemmer and his staff made hundreds of thousands of dollars by illegally dispensing the painkiller.

Clemmer will be sentenced in September.

Dr. Joseph Ferrara was recently indicted in connection with the illegal distribution of prescription drugs. He along with five others have been indicted for money laundering and dispensing drugs such as oxycodone, Adderall and Ambien.

The investigation included undercover visits by federal drug agents to the office of Clemmer. Court documents indicate he prescribed large quantities of the pain killer oxycodone after only a limited medical evaluation.

U.S. Attorney John Walsh said the motive for doctors in such cases is money.

“IF word gets out to the addicted community in Colorado that a particular doctor is handing out these prescriptions for a $250 fee the folks will come flocking in and a lot of money results,” said Walsh.

Pharmacies tipped investigators that they were getting prescriptions for the pain killers.

“These drugs, because they are so expensive, $80 or so a pill they quickly run through their resources,” said Walsh.

He said that turns the drug users to cheaper, addictive drugs such as heroin.