SACRAMENTO (CBS SF) — A 78-year-old Dublin doctor was convicted Friday of illegally prescribing opioids and other controlled substances to patients.

Dr. Edmund Kemprud was convicted on 14 counts of prescribing drugs such as hydrocodone, alprazolam and oxycodone to patients outside the usual course of professional practice and not for legitimate medical purposes, according to a press statement from Action U.S. Attorney for the Eastern District of California Phillip Talbert.

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Kemprud worked at an urgent care clinic in Dublin and also at other locations in the Central Valley, including one location in a back room of a nail salon and medi-spa in Tracy.

Evidence showed Kemprud ignored indications his patients were addicts or that they were diverting the drugs as he wrote more prescriptions for the highly addictive substances while charging $79 a visit, according to Talbert. Kemprud would write prescriptions so quickly that he often spent less than five minutes with a patient and would see 30 patients in less than a day.

Several pharmacies were so troubled by Kemprud’s prescriptions that they instituted companywide policies to block his prescriptions, Talbert said.

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“This defendant displayed a blatant disregard for patient safety and the law,” said Talbert in a prepared statement. “Although he knew his treatment of patients was unlawful, he continued to pump dangerous drugs into the community. It took the effort of agents, investigators, undercover officers, medical professionals who practiced with the defendant and pharmacists to bring an end to Kemprud’s illicit prescription writing. The U.S. Attorney’s Office will continue our vigorous pursuit of those who fuel the opioid epidemic for their own personal benefit.”

Undercover officers testified that Kemprud prescribed opioids on 14 occasions between September 2018 and March 2019 without determining the patients’ medical and prescription histories, without conducting a proper medical exam, without confirming the legitimacy of the patients’ complaints, and without assessing the risk of aberrant drug behavior.

“Fueled by greed, Edmund Kemprud went from doctor to drug dealer when he began running a prescription pill mill for powerful opioids,” said DEA Special Agent in Charge Wade Shannon in a prepared statement. “Kemprud’s actions not only preyed upon those battling addiction, but also contributed to the ongoing opioid crisis. This verdict underscores our commitment to hold unscrupulous doctors accountable for their actions.”

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Kemprud was scheduled to be sentenced in February. Although he faces a maximum penalty of 20 years in prison, the actual sentence will take into account applicable statutory factors and federal sentencing guidelines.