Seven years ago, David Franklin sued his former employer, Warner-Lambert, for illegally marketing an epilepsy drug for unapproved uses. Little did he know how much that lawsuit would unsettle his life.

The microbiologist ended up blackballed in the pharmaceutical industry and had to endure an emotionally and financially draining odyssey as a whistle-blower.

"This has been the most disruptive thing that could ever take place in someone's life," he says.

But today, at 42, Franklin is a very wealthy man. He was awarded $26.6 million as part of a $430 million settlement Pfizer — which didn't become involved until it bought Warner-Lambert four years ago — agreed to Thursday with the Justice Department and state attorneys general.

The company pleaded guilty to marketing Neurontin to treat about a dozen ailments for which it is not approved by the Food and Drug Administration and for bilking the Medicaid program. (Story: Pfizer settles fraud case)

Franklin filed his lawsuit under the U.S. False Claims Act, which allows private citizens to sue on behalf of the government and get a portion of awards in cases where firms defraud the government.

Franklin now is at the medical-device maker Boston Scientific, where he helps physicians decide how to best treat their patients. That's a dramatic departure from his four months at Warner-Lambert. "I was the individual paid to lie to doctors," Franklin says. "I got involved in something I didn't realize it was wrong at first."

Franklin says he would try to persuade doctors to prescribe Neurontin for uses including bipolar disorder that weren't proved either safe or effective. He would do so at pharmaceutical "boondoggle" weekends and other venues.

He hated what he was advocating, which he considered akin to experimenting on patients. So he started gathering documents and voice mails that would prove the company was trying to get around the law by promoting unapproved uses of the drug. After he quit his job, he took the information to attorney Tom Greene of Greene & Hoffman, who brought it to the U.S. Attorney's office in Boston, which launched a criminal investigation.

"It took a lot of courage for Dave to come forward at great risk to his professional career and his family and a tremendous amount of public good has resulted," Greene says.

After leaving the company in 1996, the usually outgoing Franklin says he had such "intense shame" about what he did while at Warner-Lambert that he became almost reclusive for about four years. He says it wasn't until the case became public and he started hearing from patients who could forgive him for what happened that he felt "reinvigorated."

Thursday's settlement gives him even more personal satisfaction — not to mention enough money that he could walk away and retire. But Franklin only plans to take his wife and two daughters on vacation. And Franklin says he is not going to be like a lottery winner who at first plans to keep working, but then changes their mind. "I am the quintessential workaholic," Franklin says. "I like to think this won't change my life."

Louis Clark, president of the Government Accountability Project, says even well-compensated whistle-blowers often keep working because settlements energize them. "Whistle-blowers are usually the hardest-working people in the office to begin with and have the highest standards, which is what led them to blow the whistle in the first place," Clark says.

Franklin says whistle-blowing isn't for everyone: "It takes real staying power."