Prosecutors estimated Healy made nearly $700,000 that year from selling controlled substances. However, authorities said they couldn't account for 75 percent of the pills purchased over a 13-month period because Healy didn't keep records of the transactions.
"There can be no doubt that he was simply a drug dealer in a lab coat," prosecutors wrote in court documents.
Defense attorney Roger Rosen contended his client made a profit of only $49,000 from selling controlled substances in 2008.
The case highlights a growing problem with prescription mediations, which rank second in popularity behind marijuana among drug users in the U.S., according to the Office of National Drug Control Policy.
Authorities portrayed Healy as a greedy doctor who didn't examine his patients - many of whom were young adults - and was looking to make a quick buck even though he knew some of his patients were addicted to prescription drugs.
Prosecutors had recommended a prison sentence of more than 17 years.
But U.S. District Judge Manuel Real said he struggled to determine an appropriate prison sentence for Healy, who had no prior criminal record and would be unable to practice medicine after his release from prison.
"It's disappointing for me and for so many people that you have helped in the past, that you would have ever put yourself in a situation in dealing improperly with drugs," Real said.
Healy also was sentenced to 10 years probation and ordered to pay $100,000 after pleading guilty last year to one count of distribution of a controlled substance, the painkiller oxycodone. Sixteen other counts were dismissed as part of the plea deal.
Slim with gray hair, Healy wore a green prison-issued jacket with white pants and showed no emotion when the sentence was read. His mother and two of his children attended the hearing.
Defense attorney Rosen said his client made a mistake by risking his livelihood to gain extra money. Rosen, however, said Healy wasn't living a lavish lifestyle.
"I can tell you from the bottom of his heart, he regrets he took that route," Rosen said after the hearing. "He realizes he should have handled it differently."
Healy had clinics in Duarte and Rancho Cucamonga where he charged his patients $25 for 30 tablets of hydrocodone, also known as Vicodin or Norco, over a three-year period, authorities said.
Healy bought the pills from two pharmaceutical companies and offered his patients "party size" or "family size" bottles of narcotics, according to court documents.
His receptionist told investigators patients would refer to Healy as the "Candy Man."
Real noted that Healy attempted to help some of his patients kick their addictions. But Assistant U.S. Attorney David Herzog said Healy would charge his patients more for the anti-addiction medication than the prescription drugs.
"At the end of the day, this doctor isn't going to prescribe any more drugs into the community," Herzog said outside court.
Healy's assistant, Alvaro Rosales, pleaded guilty to one count of conspiracy to possess hydrocodone with the intent to distribute and was sentenced to eight months in federal prison.
Prosecutors said Rosales was not licensed to practice medicine in California but prescribed and dispensed the drug to patients.