Last December, Joey Rovero and a couple of pals from Arizona State University set out on a road trip to Southern California.
They weren't headed to Hollywood or some other spot likely to attract a trio of rowdy frat boys out for a good time. Their destination was a clinic in a mini-mall off the 60 Freeway.
After a short visit with Dr. Lisa Tseng, the young men left with a handful of prescriptions and headed back to ASU. Nine days later, Rovero, a muscular former high school football star, was dead of an overdose. He was 21.
Rovero was one of at least six men in their 20s who have died of overdoses since 2007 after making the trek to Tseng's office in Rowland Heights, a Times investigation has found. Two others died after getting drugs from patients who got them from Tseng, authorities said.
Though Tseng is a general practitioner without a specialty, some patients drove from San Clemente, Palm Springs and places even farther away to see her.
Many who died were white men in their early 20s from Orange County. As kids, they played baseball and soccer and went surfing. They had nice homes and loving parents. Several shared a mischievous streak or bad-boy edge that led them to experiment with drugs.
Friends and family members of some patients described their loved ones as addicts who used old injuries — a once-shattered ankle from riding motocross, a sore knee from a snowboarding mishap or a stiff back from a car accident — as excuses to score drugs.
Tseng prescribed an array of painkillers, muscle relaxants and anti-anxiety medications, according to records. Sold under the brand names OxyContin, Vicodin, Soma and Xanax, these drugs are widely abused by teens and young adults who increasingly are ending up in detox centers, emergency rooms and county morgues.
Last week, after investigating Tseng for nearly three years, the U.S. Drug Enforcement Administration deemed her "an imminent danger to public health and safety" and suspended her license to prescribe drugs prone to abuse.
Since then, law enforcement officers have received calls from more parents alleging that their children had overdosed after getting prescriptions from Tseng.
Hsiu-Ying "Lisa" Tseng graduated from Michigan State University's College of Human Medicine with an osteopathic degree in 1996. Her California medical license remains in good standing, according to state records. She has no reported malpractice judgments against her or settlements of note and has not been charged with any crime.
Complaints about her practice from parents are another matter. Tseng, 40, of Arcadia, said she gets them "every day."
"They call me all sorts of names … drug doctor, drug-dealing doctor," Tseng said, adding that their anger was misplaced.
"I prescribe based on what I know and what I feel and what I see," Tseng said. "If it is a new patient, there is no way for me to determine … if they are legitimate or not."
Tseng spoke to The Times last week as DEA agents and state medical board investigators were inside her office seizing patient files and financial records. They raided the Rowland Heights facility as part of an ongoing probe into whether she was prescribing OxyContin and other drugs to patients with no legitimate medical need.
Tseng said those patients who died had not followed her dosing instructions.
"I never intended to kill anybody," she said.
The drugs Tseng prescribed, although addictive, can provide much-needed relief to patients in pain. The law gives doctors broad latitude to make diagnoses and treatment decisions, but requires that they conduct physicals and document a patient's medical history.
Experts say such measures should help physicians tell the difference between a patient with real pain and an addict shopping for his or her next high. Among the most obvious signs of abuse are patients willing to drive long distances to see a doctor; patients asking for a specific medication in its most potent dosage; and patients going to multiple pharmacies to have their prescriptions filled.
Tseng said she had noticed that some of her patients drove long distances to see her. She said she asked them why and was told that they had been referred by friends or relatives — an explanation she accepted.
Asked whether she believed that she had been duped into giving drugs to any patients who didn't need them, she replied: "Yes."
Tseng said she eventually noticed that "a lot" of pharmacies were questioning her prescriptions or refusing outright to fill them. Prompted by this concern and by media reports about celebrities overdosing on prescription drugs, Tseng said, she stopped writing new prescriptions for OxyContin last year.
"Now," she said, her patients "understand that they can't come in here and get anything they want."
Cases against doctors are fraught with the difficulties medical and legal authorities face in drawing the line between legitimate medicine and drug dealing.