Five New York City doctors were arrested Friday on charges that they accepted bribes and kickbacks from an Arizona-based pharmaceutical company to prescribe large volumes of a highly addictive painkiller.

The doctors allegedly were paid more than $800,000 by Insys Therapeutics Inc., according to a 75-page indictment handed up in Manhattan federal court on Friday.

They pleaded not guilty for all charges including conspiracy to overprescribe the spray version of fentanyl, a highly addictive opioid.

Prosecutors say the doctors, four men and a woman, collected tens of thousands of dollars working for the company's 'Speakers Bureau' over a four-year stretch beginning in August 2012.

Drs Gordon Freedman (left) and Todd Schlifstein were charged on Friday for conspiracy to overprescribe a highly addictive opioid to patients. They, and three other doctors, were allegedly paid more than $800,000 and bribed with other incentives

Manhattan U.S. Attorney Geoffrey S. Berman said the doctors reneged on their oath as doctors to put the care of their patients above all else.

He said they accepted bribes in the form of speaking fees in exchange for prescribing millions of dollars' worth of a potent fentanyl-based spray that is 50 to 100 times more potent than morphine and used their patients as an 'instrument for profit.'

Dr Jeffrey Goldstein is another doctor charged with conspiracy to overprescribe an addictive opioid. All the doctors are expected to be released after each paying a bond of $200,000

William F. Sweeney Jr., head of New York's FBI office, said the doctors 'were convinced to push aside their ethical obligations and prescribe a drug for profit to patients who turned to them for help.'

He said doctors and medical professionals everywhere should be reminded 'that the health and safety of their patients is not for sale.'

The doctors were identified as Gordon Freedman, 57, of Mount Kisco, Jeffrey Goldstein, 48, of New Rochelle, Todd Schlifstein, 49, of Manhattan, Dialecti Voudouris, 47, of Long Island City and Alexandru Burducea, 41, of Little Neck.

All of the doctors practiced in Manhattan, prosecutors said.

Nicholas Kaizer, a lawyer for Burducea, said he looks 'forward to the resolution of the charges in his favor.'

Other defense lawyers declined comment after the arraignment.

Prosecutors said the 'Speakers Bureau' was created with the purported intent to educate other practitioners about the fentanyl spray, but it was used instead to induce doctors to prescribe large volumes of the spray by paying them speaker program fees.

Jonathan Roper (second left), a former Insys Therapeutics Inc. sales manager, and Fernando Serrano (middle), a former sales representative at the company, walked out of federal court on Friday. They pleaded not guilty to a scheme where the company would pay doctors to overprescribe a highly addictive opioid

They said that although speakers were supposed to conduct slide presentations, the events often became mostly social affairs with no educational presentation about the spray.

Instead, these social gatherings were often just parties held at a pricey restaurant.

One benefit for Dr Gordon Freedman and Dr Todd Schlifstein included a strip club event where a senior pharmaceutical executive with Insys Therapuetics Inc. spent $4,100 on liquor and lap dances, the New York Daily News reports.

Schlifsten allegedly was so drunk at one of the events that he slurred his words, and Dr Jeffrey Goldstein smoked pot and snorted cocaine before his appearances, the indictment alleged.

The government said attendance sign-in sheets at the programs were frequently forged by the addition of names of health care practitioners who had not actually been present.

The company, Insys Therapeutics Inc., hasn't commented on the indictment.

The doctors are expected to be released after posting a $200,000 bond.