Handcuffs photographed Tuesday, December 26, 2017.

A Baton Rouge doctor pleaded guilty to receiving $336,000 in kickbacks in exchange for sending patient urine specimens to a drug testing laboratory, federal authorities said Wednesday. 

The doctor, Gray Wesley Barrow, 58, faces a "significant term of imprisonment," restitution and fines as part of the plea, U.S. Attorney Brandon Fremin's office said in a news release. 

Barrow was a co-owner of Louisiana Spine & Sports LLC, a pain management clinic in Baton Rouge. 

As part of the kickback scheme, Barrow agreed to send urine specimens collected from patients to an unnamed drug testing laboratory, according to Fremin's office. In return, Barrow received a percentage of the reimbursements paid to the lab by health care benefit programs, including Medicare. 

The arrangement spanned from April 2014 through July 2016. 

"It is especially egregious when medical doctors violate their position of trust in the community and the Medicare system to enrich themselves," Fremin, the U.S. Attorney for the Middle District of Louisiana, said in a statement.