A federal jury has convicted a physician assistant who worked at a Fountain Valley medical clinic on federal drug trafficking charges for writing prescriptions for dangerous and addictive narcotics without a medical purpose.

Kaitlyn Phuong Nguyen, 32, of San Jose, California, was found guilty yesterday of 10 counts related to the illegal distribution of oxycodone, methadone and alprazolam. The trial jury heard evidence that four “patients” died of drug overdoses after obtaining prescriptions from Nguyen.

On the eve of Nguyen’s trial last week, the doctor who oversaw the clinic was sentenced to 70 months in prison after pleading guilty to two counts of illegal distribution of a controlled substance by a practitioner.

When he pleaded guilty earlier this year, Dr. Victor Boon Huat Siew admitted illegally prescribing oxycodone, methadone and alprazolam from his clinic from the beginning of 2009 through early 2015.

Siew, 66, of Laguna Beach, was sentenced by United States District Judge James V. Selna, who presided over Nguyen’s trial.

According to court documents and evidence presented during Nguyen’s trial, Siew and Nguyen issued prescriptions without a medical purpose in exchange for cash and insurance payments. “Many of the patients…. had ‘red flags’ in their patient files, indicating that they were abusing their pain medication and should not have been given prescriptions,” according to a brief filed in relation to Nguyen’s trial.

Nguyen, who worked at the clinic in 2012, performed only cursory examinations on most “patients” prior to prescribing them narcotics. “Despite having a license to write prescriptions herself, defendant [Nguyen] usually used a prescription pad pre-signed by Siew (which was not a lawful practice) to prescribe addictive substances such as oxycodone, methadone and alprazolam,” according to the trial brief.

The most common drugs prescribed by Siew and his employees were oxycodone (best known under the brand name OxyContin), methadone (a synthetic opioid often used as a treatment for addiction to opioids such as heroin), and alprazolam (sold primarily under the brand name Xanax).

The jury found Nguyen guilty of conspiring to distribute controlled substances and nine counts of distribution of controlled substances. As a result of yesterday’s convictions, Nguyen will face a statutory maximum penalty of 140 years in federal prison when she is sentenced by Judge Selna on January 22.

A third defendant in the case – physician assistant Thanh Nha T. Pham, 31, of Fountain Valley, pleaded guilty to conspiracy to distribute controlled substances and is scheduled to be sentenced by Judge Selna on January 29.

This case is the result of an investigation by the Drug Enforcement Administration, the Fountain Valley Police Department and the California Department of Justice. The case is being prosecuted by Assistant United States Attorneys Ann Luotto Wolf and Rosalind Wang of the Santa Ana Branch Office.