Since then, hundreds of lawsuits have been filed against the drug's maker. But, as CBS News Correspondent Sharyl Attkisson reports, others who want to sue are out of luck.
Virginia Kent's decline was sudden. "When she went to the hospital,... she had no liver. In seven days, no liver!" says Joyce Johnson, her daughter.
Barbara Soukup's death took longer, but was just as devastating. "It happened way too soon, it happened way before the end of her life should have occurred and that's what's really hard to take," says her daughter, Kathy Burgess. "Someone really needs to be responsible for that."
Both of these Michigan families lost their mothers to liver failure caused, they believe, by the diabetes drug Rezulin. Like those who are suing Rezulin's maker, Warner-Lambert, they claim the company misled patients about the risks, which Warner-Lambert denies. But these families are barred from going to court.
That's because in Michigan, residents aren't allowed to sue drugmakers over Rezulin or any other drug. It's the only state in the country with such a law protecting drug companies.
I'm shocked that just because of where my mother resided, that means we have no recourse for her untimely death," says Kathy Burgess.
Attorney Douglas Peters says it's no coincidence that Michigan has this unique law, since several pharmaceutical and medical firms have divisions here -- including Warner-Lambert.
Peters believes that "If you're run over by a negligent driver, you don't want to find out that driver has immunity simply because you got hit in Michigan!"
Michigan Governor John Engler defends the law, saying if drugs are FDA approved, drug companies shouldn't be liable.
Peters doesn't care what the law says; he's suing Warner-Lambert. The case is likely to be dismissed, but he plans to challenge the Michigan law on appeal.
"Laws were made," says Joyce Johnson. "Laws can be changed."
Changing any law isn't easy. But the families say it's worth the fight, because what happened to their mothers, is more important than where they happened to live.