Plump, soft-spoken and looking all of her 72 years, Dr. Jasna Mrdjen seems more like someone whose name and grandmotherly face would appear on a cookie package than on a court docket for drug dealing and homicide.

But the embattled Los Gatos doctor is at the center of what is believed to be the Bay Area’s first case in decades in which prosecutors are seeking to convict a physician of manslaughter for prescribing narcotics to a struggling addict who overdosed and died.

Prosecutors asking a judge to order her to stand trial presented evidence in court last week suggesting Mrdjen (pronounced merge-jen) freely prescribed addictive painkillers with little regard for whether her patients needed them, abused them or even sold them on the black market.

“It’s very difficult to work your way up the chain from the pill rings on the street to the dirty doctors,” said Patrick Vanier, the prosecutor in charge of the Santa Clara County District Attorney’s narcotics unit. “The Mrjden case is one where we were successful.”

Though the coroner blamed the January 2012 death of her patient Steven English on multiple drug ingestion, including the painkillers she prescribed, Mrdjen denies responsibility. The doctor claims English died of a cocaine overdose in Truckee nine days after he got out of the Betty Ford drug rehabilitation center. She has also pleaded not guilty to 12 other felony charges, including dispensing a controlled substance to an addict, knowingly issuing a prescription that is not for a legitimate medical purpose and conspiracy. If she is convicted, she would face a range of possible sentences, from probation to 13 years behind bars. She was in jail for a year before bailing out and agreeing to surrender her medical license.

The case against Mrdjen, who resides in Mountain View and practiced out of a Los Gatos clinic, comes as an epidemic of fatal overdoses involving prescription drugs supplied by doctors sweeps the country.

More than 40 people a day die from taking too many prescription painkillers like oxycontin, according to the Centers for Disease Control and Prevention. Yet the California Medical Board suspended or revoked the licenses of only 14 of the state’s 137,500 doctors last year for excessive prescribing.

Though still rare, homicide cases against doctors whose patients overdose on painkillers are on the rise nationwide since 2011. That’s when pop star Michael Jackson’s physician, Dr. Conrad Murray, was convicted of involuntary manslaughter for giving the insomniac singer a fatal overdose of the surgical anesthetic propofol to help him sleep. Murray served two years in jail.

But such cases can be tough to prove. In Iowa last year, Dr. Daniel Baldi was acquitted of involuntary manslaughter in the deaths of seven of his patients, including Paul Gray, an internationally known musician who co-founded the metal band Slipknot.

“There’s an element of personal responsibility prosecutors ignore,” said Baldi’s lawyer, Guy R. Cook, who is critical of criminalizing such deaths. “What’s unfortunate for the doctors is that the great majority of patients are people with chronic pain, and then there’s a small group of people who abuse the system.”

In Chicago, however, federal prosecutors won a case against Dr. Paul Volkman, who was sentenced in 2012 to four life terms for the overdose deaths of four people. In a pending multiple-death case in Los Angeles County, Dr. Hsui-Ying “Lisa” Tseng is charged with second-degree murder in connection with three fatal overdoses, including a 21-year-old San Ramon college student, Joey Rovero.

“These doctors are basically legal drug dealers,” said Joey’s mother, April Rovero, who formed the National Coalition Against Prescription Drug Abuse with her husband after her son’s death.

Rovero said that trying to stop the abuse via the courts may deter some doctors but will never be as effective as other strategies. She supports a current bill by state Sen. Ricardo Lara, D-Bell Gardens, that would require prescribers to check an existing state database before prescribing the most addictive medications to patients, many of whom go to more than one doctor for prescriptions.

New details about how easy it was to get painkillers from Mrdjen — and how one of her patients brazenly sold some of the pills he got to an undercover cop for about $27 apiece — emerged in Santa Clara County Superior Court last week. Judge Andrea E. Flint is expected to decide after hearing more testimony next month if there is enough evidence for Mrdjen to stand trial.

Before English died, Mrdjen was already under investigation for writing excessive prescriptions by the Santa Clara County Specialized Enforcement Team, a task force of several law enforcement agencies. Some of the addicts would then pick up the bottles at a pharmacy and turn a sizable profit by selling each $8 pill for more than three times as much as the retail price, authorities say.

Last week, prosecutor Dana Veazey played an incriminating tape that was secretly recorded by Santa Clara police Officer Douglas Gerbrandt, who posed as a construction worker with a backache during four visits to the clinic in the summer of 2011. He paid Mrdjen a $100 fee per visit, and in less than three months, she gave him prescriptions for 870 oxycontin and oxycodone without ever taking his pulse, blood pressure or medical history.

On the tape of one of the visits, Mrdjen expressed concern to Gerbrandt that “the government” was cracking down on her for writing too many prescriptions for narcotics. She also advised Gerbrandt to avoid certain pharmacies that might refuse to serve him or be under surveillance by the authorities in Palo Alto, Redwood City and Watsonville, and counseled him on how to pass a urine test.

During a court break last week after the tape was played, Mrdjen ignored her attorney Guy Jinkerson’s advice and told this newspaper without being prompted that she had been in terrible health when she treated Gerbrandt. She was taking steroids for severe asthma, she said, which caused her to balloon up to about 300 pounds, which in turn worsened her narcolepsy. She also said she’d had a stroke while she was seeing patients two afternoons a week in her small, two-room clinic in an office building on Los Gatos’ Capri Drive.

“I was out of it,” she said, noting that the 45-minute tape captures her speaking in a rambling manner punctuated by long pauses in which she contends she briefly fell asleep.

But on the tape, she also clearly refers to the FBI and DEA as a “pain in the neck” and says she’s not taking new patients “till things cool.”

Contact Tracey Kaplan at 408-278-3482. Follow her at Twitter.com @tkaplanreport.