San José doctor convicted of 12 counts of illegally prescribing and distributing opioids

Prescription bottle and white pills
San José physician Donald Siao wrote 8,201 prescriptions for oxycodone, hydrocodone and other powerful controlled substances in one year, prosecutors said.
(Tom Kelley / Getty Images)
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A San José physician was convicted of illegally prescribing and distributing large quantities of opioids without a legitimate medical purpose, including to one person who died of an overdose, federal prosecutors announced Friday.

Donald Siao, 58, a family physician, was convicted by a federal jury on Tuesday of 12 counts of distributing the controlled substances oxycodone and hydrocodone outside the usual course of his medical practice over a 12-month period between 2016 and 2017, prosecutors with the U.S. Attorney’s Office said in a news release.

After identifying Siao in a separate prescription fraud investigation, investigators discovered Siao had written 8,201 prescriptions for controlled substance medications in just the one-year period from May 2016 to May 2017, according to prosecutors. During the course of the investigation, Siao prescribed increasing amounts of opioids to four separate undercover agents posing as patients, even though in some instances they admitted to sharing the drugs with co-workers or friends.


Each of the 12 counts against Siao carries a maximum sentence of 20 years in prison. Ismail J. Ramsey, the U.S. attorney for the Northern District of California, announced on Friday he would seek to have Siao’s medical license forfeited.

Calls to the U.S. Attorney’s office and to Siao’s lawyer were not immediately returned.

Eight of the 12 counts against Siao involved a mother and son identified in court documents as E.J. and A.J., respectively.

Both mother and son claimed to have lost or had pills stolen and Siao continued to respond with prescriptions, according to court documents.

Siao also ignored a warning from an insurer about potential fraud regarding E.J. and a notice that A.J. had previously been arrested for selling pills, prosecutors said in the news release.

A.J. overdosed twice but still received prescriptions from Siao, according to court documents. A.J. died from an overdose of opioids in December 2019. In addition, Siao did not comply with medical records requests from the coroner following A.J.’s death.

The last four counts against Siao were related to an operation conducted by an undercover interagency task force.


The California Department of Justice Bureau of Medi-Cal Fraud and Elder Abuse, or BMFEA, was one of several agencies investigating Siao in 2017, according to court documents. In May of that year, the agency searched a state controlled substance database and found that Siao had written more than 8,000 prescriptions for controlled substances.

Many of those prescriptions called for 30 milligrams of oxycodone, which is at the higher end of dosage strength. The National Library of Medicine states, for instance, that immediate-release oxycodone tablets begin at 5 mg and top out at 30.

Along with oxycodone, Siao issued prescriptions for combinations of opioids, muscle relaxers and benzodiazepine, often known as the “Holy Trinity,” according to court documents. The Department of Justice has said the trio taken together “depress the central nervous system and the ability to breathe.”

The drug task force conducted an investigation from February to May 2018. Four agents visited Siao’s office multiple times to request prescriptions for controlled substances.

In one case, one agent known as A.M. pretended to be a retired football player who complained of pain in his shoulder, arm and elbow. He saw Siao three times, with each visit ending with a prescription.

In his third appointment with Siao in July 2018, A.M. admitted he had shared a portion of a previous 60-tablet, 30-mg strength oxycodone dosage, a potentially addictive controlled substance used for pain management, with a co-worker. The agent asked if Siao could increase the amount of pills to compensate for the borrowed cache.


Siao obliged and increased the total to 75 pills at an appointment that lasted approximately two minutes, according to court documents.

Another agent, identified only as E.T. in court documents, sought Siao for a prescription of Norco, a combination of hydrocodone and acetaminophen used for pain management.

The agent said he had previously purchased Norco at work for $10 a pill. Siao said, “That is nuts,” according to court documents. The doctor then added, “I’m not going to say anything. Some people try to make a business out of that; put it that way.”

The physician then prescribed 45 tablets of 10-mg strength after a first visit in April 2018, according to court documents.

Siao eventually increased the amount to 60 tablets upon E.T.’s second visit, prosecutors said. He also prescribed a cannabinoid, Marinol, at the agent’s request. The agent told Siao he was a marijuana user and needed to show his employer that any cannabis found in his blood stream through random testing was due to another drug.

Siao replied “gotcha” and filled out the prescription, prosecutors said.