Antibiotic Tequin Found To Cause Serious Blood Sugar Problems In Older Patients

New Finding From Canadian Studies: Increased Risk Of Hypoglycemia and Hyperglycemia Not Limited To Diabetics

Elderly patients taking the widely-used antibiotic Tequin are almost 17 times as likely to be hospitalized for very high blood sugar levels (hyperglycemia) and four times as likely to be hospitalized for unusually low levels (hypoglycemia). This is according to results from two recently concluded Canadian studies involving Tequin, which are the subject of a March 2006 article in The New England Journal of Medicine (NEJM). The finding is leading some doctors to call for the withdrawal of Tequin from the market. The NEJM published an editorial written by one doctor who wants a Tequin recall in the same edition as the article about the alarming results from the Canadian studies.

Overall, one of every 100 patients who took Tequin was hospitalized according to the March 2006 NEJM article about the two Canadian studies. Both hypoglycemia (low blood sugar) and hyperglycemia (high blood sugar) can induce coma and other serious problems, including death. Symptoms usually began five to 10 days after patients took the drug. Because these abnormal blood sugar conditions are potentially fatal, they need to be treated promptly. Fortunately, in most cases the symptoms can be reversed when the Tequin use is stopped.

Tequin was approved by the FDA in 1999. By 2001, 3.3 million prescriptions per year were being written for Tequin. By 2003, however, the FDA had received reports of 17 deaths in patients who received Tequin, and prescriptions were down to about 1.7 million per year.

Who Is At Risk?

Before the March 2006 NEJM article, there were reports of several previous studies which had shown Tequin is associated with an increased risk of blood sugar, or glucose, abnormalities. In part due to these earlier studies, the label, or package insert, was changed in February 2006 to warn that Tequin should not be given to diabetics. At the same time, Bristol-Myers Squibb sent a "Dear Doctor" letter to not only emphasize the addition of diabetes mellitus as a contraindication but, in addition, to caution that special care should be taken in the use of Tequin among elderly patients, “who may have unrecognized diabetes, age-related decrease in renal function, underlying medical problems, and/or are taking concomitant glucose-altering medications” — circumstances that could place the patient at an increased risk for developing possibly harmful changes in blood sugar levels.

What is particularly signigicant about the recent Canadian studies -- which were larger and regarded as more definitive than any earlier Tequin study -- is the finding that all older patients were at risk, even those who were not diabetic. This finding caused one of the lead reseachers for the Canadian studies to urge doctors to stop prescribing Tequin. "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, because other antibiotics were as effective and had better drug-safety profiles.

Dr. Sidney Wolfe, of the Public Citizen Health Research Group, has suggested that a recall of Tequin is in order. Dr. Wolfe said: "This represents a unique danger in the absence of a unique benefit…. This is more than enough reason to think about petitioning the Food and Drug Administration to ban [Tequin], and we probably will."

In February 2006 the FDA and Health Canada, both, issued drug-safety alerts about Tequin in connection with the release of the alarming findings from the two Canadian studies.

Tequin is a member of the class of broad-spectrum antibiotics known as fluoroquinolones. Tequin is typically used to treat gonorrhea as well as lung, sinus, and urinary tract infections. In addition, doctors often use Tequin when the nature of an infection is unknown because it kills a wide variety of bacteria.

Read more on our Tequin Information Page >>