The Food and Drug Administration recommends that diabetics who use the new drug Rezulin get repeated liver tests after it linked the medicine to rare but potentially serious liver problems.
The FDA said Monday it had received 35 reports of liver injuries from among the estimated 500,000 Americans treated since the drug went on sale last spring. Problems ranged from mildly elevated liver enzymes to liver failure that led to one transplant and one death.
The FDA cautioned that Rezulin may not be solely responsible because some patients had other risks.
But manufacturer Warner-Lambert Co. agreed to change the drug's label to warn about the liver reaction and recommend testing and wrote doctors nationwide about the warning.
Rezulin, known chemically as troglitazone, is used by Type II, or adult-onset diabetics. It can help resensitize the body to insulin, allowing many patients to reduce their daily shots of the vital hormone.
The FDA recommended that doctors test the blood of Rezulin users within the first one to two months of therapy to see if they have elevated levels of liver transaminase enzymes. Patients then should be tested every three months for the first year of therapy, as should any patient with such symptoms as vomiting, abdominal pain, fatigue, loss of appetite or dark urine, the FDA said.
Patients suspected of liver dysfunction _ expected to be about 2 percent of Rezulin users _ should stop taking the drug, the agency said.
Few, if any, of these patients will go on to develop permanent liver damage if the drug is stopped, the FDA said.