Now, the FDA's advisory committee is looking at whether the drug should stay on the market.
"Apply your sharpest scientific thinking and bring your best judgment to the questions facing the agency," said FDA commissioner Margaret Hamburg.
The most recent analysis presented Tuesday at the FDA meeting estimates that as many as 100,000 heart-related problems may have been caused by Avandia.
GlaxoSmithKline maintains the drug is safe.
One issue with an earlier study is that doctors tracking patients were aware of which patients were getting Avandia, and which one were getting different diabetes drugs. And that could have set up a bias, influencing results.
There are dozens of diabetes medications on the market, but Actos is the only other drug that works the same way Avandia does.
Critics say there's no reason to leave a potentially dangerous drug on the market, when Actos provides similar benefits, without the potential heart risk.
Since diabetics are already predisposed to heart risks it can be difficult to tell which heart attacks are drug related and which are a result of the diabetes.
On Wednesday, the FDA's committee will ask a panel of outside experts for their comments. The advisory committee will then vote on a recommendation which could include banning the drug. The FDA will make a final decision in coming months.