Michael Alston Smith, whose family practice in Mount Holly, North Carolina, is now closed, has enrolled in truck driving school to pay his bills, court documents show. The North Carolina Medical Board suspended his license to practice medicine last October .

Smith pleaded guilty in U.S. District Court in Charlotte on Friday to drug distribution, health care fraud and aggravated identity theft. The charges carry a maximum combined penalty of more than 20 years.

Smith was freed on $25,000 bail on Friday pending his sentencing hearing, which has yet to be scheduled. He has agreed to pay the government a $150,000 civil penalty, records show.

The charges stemmed from “the illegal distribution of controlled substances to female patients in exchange for sex acts,” the U.S. Attorney’s Office in Charlotte said in a statement.

Smith regularly billed Medicaid and Medicare for reimbursement for patient visits in which sex — but no medical treatment — took place, prosecutors said. The patients who received Smith’s fraudulent prescriptions likewise submitted government claims to cover the costs of their drugs, according to court records.

Smith practiced alone at his Mount Holly Family Practice Inc. He also got permission from the federal Drug Enforcement Administration to run an opioid treatment program at his office, where he treated “a large number” of patients for substance abuse and pain, according to prosecutors.

His drugs-for-sex encounters started in January 2017 and occurred over 10 months, court records show. He treated the women for such conditions as anxiety disorder, opioid dependence, chronic back pain, depressive disorder and schizoaffective disorder, bipolar type, according to the North Carolina Medical Board.

In August 2017, Smith made a woman seeking treatment for opiate addiction have sex with him in an examination room while the woman’s 3-year-old daughter was present, prosecutors said.

Afterward, Smith upped the woman’s dosage of Clonazepam, a powerful sedative and popular recreation drug, without giving her an exam, court records show.

On Sept. 11, the same patient returned to an exam room at Smith’s office, this time with her 3-month-old son, according to court documents. After the sex acts, Smith signed over new prescriptions for Clonazepam and Buprenorphine HCL, a drug used to treat opiate addiction.

The next day, the doctor submitted a $78.76 reimbursement claim to the N.C. Medicaid program for the woman’s visit, records show. Medicaid paid out another $131.60 for the woman’s fraudulent prescriptions.

In January 2017, Smith propositioned another patient he was treating for addiction and pain management. The woman initially refused his solicitations, but Smith persisted and threatened to cut off her treatment, court records show. The woman relented and had sex with the doctor over the next 10 months at his office, according to documents. Each time, Smith prescribed her drugs “without performing any medical examination,” the documents show.

Smith’s fraud cost government health programs at least $10,000, prosecutors said.

In a statement Friday, North Carolina Attorney General Josh Stein said Smith “caused immense harm to patients struggling to combat opioid addiction, and in the process, cheated Medicaid and wasted taxpayer money. My office will continue to investigate and prosecute health care providers who commit fraud and abuse.”