DENVER – A Denver doctor has pleaded guilty to illegally prescribing a dangerous combination of controlled substances known as the “Holy Trinity.”

The Denver Post reported Thursday that 54-year-old Andrew Mark Ho entered his plea Wednesday and agreed to 15 years of supervised release and relinquished his ability to prescribe controlled substances.

Prosecutors say the “Holy Trinity” includes muscle relaxers and opioids and is dangerous because it depresses the central nervous system and affects a person’s ability to breathe.

Prosecutors said Ho prescribed a combination of controlled substances between 2014 and 2016 “outside the scope of accepted medical practices.”

Efforts to reach Ho and his attorney were unsuccessful.

Health regulators said Ho’s medical license is active but with restrictions.

He is expected to be sentenced in January.