Gladys Mensing can no longer control the muscles in her tongue, face, arms and legs. It's hard for her to speak and nearly impossible for others to understand her. She can no longer live on her own.

The 76-year-old Owatonna woman has an untreatable neurological disease known as tardive dyskinesia that she traces to a generic drug taken a decade ago.

On Wednesday, Mensing's claim went before the U.S. Supreme Court, though she was too sick to be there. "I've been through an awful lot," Mensing said earlier this week.

When it comes, the court's ruling will put a Minnesota stamp on a case that could affect the entire $77 billion generic drug industry. Generics now account for more than two-thirds of all prescription drugs sold in the United States, according to the Generic Pharmaceutical Association.

The nine justices heard arguments on whether generic drug companies can be sued for failing to warn of known dangers under state law when federal law requires only that generic drugs carry warning labels identical to brand-name equivalents.

In her suit, Mensing is relying on a Minnesota law that requires drugmakers to warn of the risks. Generic drug manufacturers say the state law should be superseded by federal labeling laws. There are thousands of lawsuits like Mensing's nationwide awaiting the court's ruling.

'I can't do anything'

While the industry waits, Mensing's family ordeal continues.

Harvey Mensing, her brother, said that he limits the time he spends with his sister. "Not because I don't love her," he said, "but I cannot stand the helpless feeling I have that I can't do anything."

Gladys Mensing began taking metoproclamide, a generic version of the drug Reglan, in 2001 to treat a stomach disorder. Reglan was first approved in 1980. By the mid-1980s, the drug went into generic production only.

When Mensing started taking the metoproclamide, the warning labels did not say that long-term use carried a 20 percent risk of the disorder that now affects her. The U.S. Food and Drug Administration required generic manufacturers to add the warning in 2009, noting that the drug should be not be taken longer than 12 weeks. Mensing alleges that medical studies published well before 2001 identified that risk but that the generic drug companies did not alert the FDA.

Mensing, a former apartment manager, took metoproclamide for four years. Then she began to notice early symptoms of tardive dyskinesia, like uncontrollable lip smacking. Quickly, she began losing control of her muscles: She was unable to stop her tongue from going in and out of her mouth, unable to stop her legs from walking.

Her son, Richard Mensing, said she had to quit working and soon could not drive. Gladys Mensing stopped going to church and the grocery store, horrified by people's stares. She wound up in the hospital once after a bad fall.

Mensing's mind is sharp, her family says, but her speech impediment and facial movements make people think she is developmentally disabled. Mensing's family now cares for her around the clock.

"I bathe her, help her get dressed in the morning, help her out of the chair, fix her food," said Roxanne Mensing, her granddaughter. "It's really taken a hit on all of us, and her especially."

Mensing filed lawsuits in 2007 against the generic drug companies Pliva Inc. and Actavis Elizabeth LLC and against several brand-name makers. Both lawsuits initially were dismissed in U.S. District Court: the brand-name manufacturers because Mensing didn't take their drugs and the generics because they were federally required only to carry labels identical to the brand-name drug.

But the Eighth Circuit Court of Appeals overturned the dismissal against the generic companies, saying they could be held responsible. The drugmakers appealed to the Supreme Court, challenging Minnesota's law.

Minnesota Solicitor General Alan Gilbert led a brief submitted by 43 states in favor of Mensing's side, arguing that states need to keep their consumer protections in place.

State vs. federal law

Generic drug company attorneys argue that they are not responsible for identifying potential side effects because the FDA says they must mimic brand-name drugs -- all the way down to carrying identical warning labels.

Jay Lefkowitz, who argued the case Wednesday for the drugmakers, told the justices that federal law instructs companies to tell the FDA if they think a label change is needed. "The FDA will then make a decision, which makes clear that this is not a decision for state juries to make," he said.

Justice Sonia Sotomayor questioned whether the drug companies were trying to say they bore no responsibility for telling the FDA about problems.

"There is a legal obligation to advise the FDA when you have reports of adverse results that suggest the label may be wrong," Sotomayor said. "Are you disavowing your obligation to tell the FDA when something's wrong?"

But Justice Antonin Scalia asked whether generics should have the same responsibilities as brand-name drugs when they don't have the same testing standards. "This is a generic manufacturer. He doesn't know anything about science -- he knows how to replicate this pill exactly," Scalia said, using a hypothetical scenario. "Now what is the test you're going to impose to a jury to decide whether this generic manufacturer ought to have proposed a labeling change?"

The companies also argue that Congress created generic laws to provide cheap drugs and that requiring the same testing conducted by brand-name manufacturers would drive up costs.

Mensing's attorneys counter that generic drugmakers have a responsibility to tell the FDA about known risks. Louis Bograd, who argued Mensing's side, told reporters: "There's a serious question about who would be minding the store."

Jeremy Herb • 202-408-2723