A doctor convicted of murder for prescribing exorbitant amounts of painkillers that left three patients dead was sentenced Friday to 30 years to life in prison.

The conviction of Dr. Hsiu-Ying ‘Lisa’ Tseng, 46, was rare for a doctor. It came after a dozen of her patients died.

Tseng prescribed ‘crazy, outrageous amounts of medication’ to patients who didn’t need the pills, Deputy District Attorney John Niedermann told jurors during her trial.

The doctor repeatedly ignored warning signs even after several patients died.

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Dr. Hsiu-Ying ‘Lisa’ Tseng was convicted of murder for prescribing exorbitant amounts of painkillers that left at least three patients dead and has been sentenced to 30 years to life in prison. Above she is pictured in court Friday during sentencing

Tseng prescribed ‘crazy, outrageous amounts of medication’ to patients who didn’t need the pills, Deputy District Attorney John Niedermann told jurors during her trial. Above she is pictured in court Friday during sentencing

Defense attorney Tracy Green, left, comforts Dr. Tseng, as she is sentenced in court on Friday in California

‘Something is wrong with what you’re doing if your patients are dying,’ Niedermann said.

While in court Friday, she apologized for her actions.

‘I’m really terribly sorry,’ she told the courtroom audience which was crowded with victims’ relatives. ‘I have been and forever will be praying for you. May God bless all of you and grant comfort to all who have been affected by my actions.’

Tseng was charged with just three killings because other factors were involved in some of those deaths, such as drugs prescribed by other doctors and a possible suicide.

Her lawyer said the 46-year-old doctor had been naive to prescribe so many medications and didn’t think her patients would abuse them.

April Rovero, the mother of victim Joey Rovero, spoke to reporters after Dr. Tseng was convicted of second-degree murder in his death and the killings of two other patients in October