As a district sales manager for Insys Therapeutics, Jeffrey Pearlman led a team that aggressively pushed doctors to widely prescribe the company’s addictive opioid painkiller Subsys. He even threatened to stop paying a nurse speaking fees if she didn’t help boost sales of the drug, e-mails show.

All the while, Pearlman held a secret: He himself was addicted to opioids like the very ones he was promoting.

Pearlman’s daily regimen of painkillers included the highest doses of his company’s own product. In extraordinary court filings, he details a miserable — and increasingly fruitless — odyssey to get pain relief from these opioids following a debilitating car accident. The pain subsided only when he stopped using opioids and turned to marijuana.

Subsys is a prescription form of fentanyl, and the risk of addiction is so strong that it is regulated by a special program at the Food and Drug Administration. The drug can cost tens of thousands of dollars a year, and Insys was subsidizing the cost of Subsys for Pearlman until the company fired him in late 2015, according to court filings.

Pearlman was also taking OxyContin three times a day and multiple Percocets daily. All of the drugs were legally prescribed, according to Pearlman.

“What happened with this guy, while his situation is interesting and ironic, is no different than millions of others who have gotten into deep trouble because of tolerance and increasing doses and false teachings about opioids from the early 1990s,’’ said Dr. Gary Franklin, a University of Washington researcher who has studied long-term use of opioids for conditions like back pain.

Pearlman was indicted in February for allegedly participating in an illegal campaign to persuade doctors to prescribe Subsys, including for patients who don’t suffer the severe “breakthrough’’ cancer pain that the drug was approved to treat.

Documents in the case say Pearlman recently began using marijuana, which he describes as a far cheaper and more effective treatment for his pain.

While he has a medical marijuana card from his home state of New Jersey, his ability to continue using the drug is threatened by the requirements of his bail. Many states have legalized medical marijuana, but the drug remains illegal under federal law. Pearlman has filed a motion in US District Court in New Haven to remove drug testing as a condition of his bail so that he can continue using marijuana.

“If Mr. Pearlman is now denied access to medical marijuana treatments while on bail, he would likely be forced to revert to the use of these opioids again — and face the renewed threat of addiction as well as harmful side effects,’’ according to the motion filed by his lawyers in federal court.

A decision on his request is pending. In the meantime, Pearlman has been drug tested and continues to use marijuana.

A spokeswoman for the Administrative Office of the US Courts said the agency couldn’t comment on specific cases. However, the courts have advised federal probation chiefs that “even when states have legalized marijuana possession for compassionate medical use, the federal prohibitions against possession, use, and distribution remain in effect.’’

Pearlman declined to be interviewed for this story. Insys did not respond to a request for comment.

A car accident more than 20 years ago left Pearlman with a severe injury to his spine that still causes him severe and chronic back and leg pain, according to the court records.

Pearlman reported that opioids made him “foggy’’ at times, and that he had difficulty remembering events, people, and other details. The drugs also caused psychological side effects, making him anxious and depressed. He also suffered physical symptoms, including a racing heart, inability to sleep, and gastrointestinal distress.

Last summer, Pearlman went through an excruciating, monthlong detoxification from opioids.

“The path to break his addiction was painful, both physically and psychologically,’’ Pearlman’s lawyers wrote in a court filing. “Mr. Pearlman barely slept for a month, had constant nausea and the shakes, experienced extremely high anxiety, felt like his skin was crawling, and sweated profusely throughout the period.’’

Pearlman was successfully weaned off opioids.

“Since stopping opioids and starting medical marijuana, Mr. Pearlman has had a great reduction in pain, without the harmful side effects associated with opioids,’’ according to a court filing.

To not allow him access to marijuana while the charges against him are pending could force Pearlman to choose between turning again to the addictive opioids or living with “debilitating pain,’’ a scenario his lawyers contend would be both “horrendous’’ and “inhumane.’’ They also argue such a situation would impair his constitutional right to participate in his own defense.

He has pleaded not guilty to one count of participating in a kickback scheme to get health care practitioners to prescribe Subsys.

The indictment alleges Pearlman oversaw an illegal and successful effort to get an advanced practice nurse in Connecticut to write more prescriptions of Subsys. To induce the nurse to prescribe more, Pearlman was part of an alleged conspiracy that paid her $83,500 to participate in a sham “speaker program.’’

Pearlman joined Insys in 2012 and quickly rose to district sales manager, overseeing sales for much of the Northeast. He was fired in December 2015. Prior to joining Insys, Pearlman, 49, sold home aquariums and ran a ticket brokerage business.

Insys faces a myriad of state and federal investigations into its sales practices.

In December, the former chief executive of Insys and several other former company officials were arrested on federal charges of conspiring to bribe doctors to prescribe Subsys. The officials have pleaded not guilty.

The indictments and investigations of Subsys marketing have clobbered the stock price of Insys, and Subsys sales have sharply declined.

The company is now betting much of its future on a new drug called Syndros. The drug is a synthetic cannabinoid, a class of drugs comprised of chemicals related to those found in the marijuana plant.

David Armstrong can be reached at david.armstrong@statnews.com. Follow David on Twitter @DavidArmstrongX.