Antibiotic Found to Cause Blood-Sugar Ailments in Seniors

Elderly patients taking the widely used antibiotic gatifloxacin were almost 17 times as likely to be hospitalized for very high blood sugar levels and four times as likely to be hospitalized for unusually low levels, a finding that is leading some physicians to call for the drug's withdrawal from the market.

Overall, one of every 100 patients who took the drug was hospitalized, according to a study released online Wednesday by the New England Journal of Medicine. The study was released before its March 30 publication because of its health implications.

Several previous studies have shown an increased risk of glucose abnormalities and several deaths in diabetic patients who received the antibiotic, trade-named Tequin. The drug's label was changed last month to say it should not be given to diabetics.

The latest study, which is larger and more definitive, showed that all patients were at risk, even those who were not diabetic.

The study's authors said that because other antibiotics were as effective, there was no reason to continue prescribing gatifloxacin.

"Speaking as a clinician, I would never prescribe this drug," said Dr. David N. Juurlink of the Institute for Clinical and Evaluative Sciences in Toronto, who led the study.

Dr. Sidney Wolfe of the Public Citizen Health Research Group in Washington, D.C., said: "This represents a unique danger in the absence of a unique benefit

Eric Miller, a spokesman for Bristol-Myers Squibb Co., which makes Tequin, said that the findings "were consistent with the post-marketing experience we have had to date." He said the labeling changes in February took the findings into account.

Miller said the company's annual sales of the drug were about $100 million in the United States and $150 million worldwide -- a relatively minor portion of Bristol-Myers' $19.4 billion in total revenue.

Gatifloxacin is a member of the family of broad-spectrum antibiotics known as fluoroquinolones. It is typically used to treat gonorrhea and lung, sinus and urinary tract infections. Physicians often use it when the nature of an infection is unknown, Juurlink said, because it kills a wide variety of bacteria.

But the quinoline family has proved problematic. Four other fluoroquinolones have been withdrawn from the market or had their use severely restricted: temafloxacin, for causing red blood cell damage, kidney failure and hypoglycemia; grepafloxacin and sparfloxacin because of heart problems; and trovafloxacin because of liver damage.