A New Jersey doctor who authorities said referred to himself as the "El Chapo of Opioids" prescribed painkillers without seeing the patients who were receiving them, often communicating via text message, and falsified records to cover his tracks, according to a criminal complaint released Monday.

Robert Delagente was scheduled to appear in court Monday afternoon. The Oakland-based Delagente is charged with distributing a controlled dangerous substance and obstruction.

The U.S. attorney's office alleges that for the last five years, Delagente used his practice, North Jersey Family Medicine, to illegally prescribe opioids for patients, often allowing them to choose their own dosage.

According to the criminal complaint, one patient received nearly 500 doses of Percocet, Oxycontin and other opioids over a seven-week period without visiting Delagente's office. One week after receiving a 10-day supply of Percocet and a 30-day supply of clonazepam, the patient texted that the medication wasn't "working like it used to." Delagente then prescribed an additional 30-day supply of Oxycontin and a 25-day supply of Percocet, the complaint alleges.

Another time, he allegedly texted a patient that he was sending the patient's prescription on a different day than a similar prescription to the patient's mother "to not draw any suspicion."

The complaint also charges Delagente with altering medical records to hide his activities.

Both charges are punishable by up to 20 years in prison.

The complaint also alleges Delagente didn't monitor whether his patients were becoming addicted to the painkillers, and prescribed the drugs to people he knew were already addicted.

An attorney listed as representing Delagente didn't immediately return an email seeking comment on the charges.