Rezulin was developed and marketed by Warner-Lambert Co. and Parke-Davis as a treatment for type 2 diabetes. Rezulin improves the body's efficiency in using insulin, thus helping with glucose control.
This medication proved to be very popular. Of the approximately fifteen to twenty million Americans with type 2 diabetes, approximately one million started to take Rezulin shortly after its 1997 approval for public use by the Food and Drug Administration. Even at this time, it was known that Rezulin was associated with liver damage in some users.
Although regular testing was instituted to check Rezulin users for liver health, with tests approximately once per month, some users experienced very rapid onset of liver toxicity, with the condition appearing within the weeks between scheduled tests.
Negative health consequences from Rezulin use include liver failure, necessitating liver transplant or causing death. Symptoms of liver toxicity associated with Rezulin include jaundice, nausea, abdominal pain, loss of appetite, fatigue, and darkened urine.
If these symptoms appear, any person who has used Rezulin should immediately contact a doctor. There have been at least thirty-eight cases of acute liver failure among Rezulin users.
In March, 2000, following a safety review by the Food & Drug Administration (FDA), Warner-Lambert/Parke-Davis announced that it was voluntarily withdrawing Rezulin from the market. The FDA's comparison of Rezulin to other similar drugs revealed Rezulin to be significantly more dangerous than available alternative medications, and determined the risk of Rezulin use to be unacceptable.
More than one hundred class action suits were filed against Warner-Lambert Co. and Parke-Davis, with many resulting in multi-million dollar settlements.