Faulty results with certain blood sugar tests

The US Food and Drug Administration is warning diabetes patients that certain blood sugar tests can give inaccurate results in patients taking other medications.

Public health regulators told consumers not to use certain glucose testing strips from Switzerland’s Roche, Abbott Laboratories and other companies in combination with dialysis and other biologic drugs. According to FDA, those formulations can elevate blood sugar level results falsely, raising the risk of insulin overdose.

People with the disease often have to inject insulin, which helps break down carbohydrates, because their bodies have become resistant to the protein.

Dialysis and so-called immunoglobulins are most often taken by patients with serious medical ailments, including kidney failure and rheumatoid arthritis. The biologic drugs’ labeling already warns that they can interfere with glucose monitoring tests, but the FDA says the products continue to be used together despite past warnings.

Since 1997 the FDA received 13 reports of death related to the use of glucose testing strips and biologic drug formulations.

“Six of the deaths have occurred since 2008 despite FDA’s efforts to communicate the risk,” the agency said. In some cases, patients experienced brain damage, coma and confusion before death. In a letter issued Thursday, the agency urged doctors and nurses to report any suspected problems related to glucose strips.

Many of the testing strips are used in hospitals and nursing facilities, “which should instead use a laboratory assay to measure a patient’s glucose if the patient is also receiving an interfering product,” the FDA said in a statement.

Brands affected by the announcement include Roche’s Accu-Chek Comfort Curve test strips and Abbott’s Freestyle test strips.

A spokesman for North Chicago-based Abbott said the company has been working on a new version of the Freestyle that deal with the problems cited by the FDA. Abbott expects to submit a marketing application for the new product to FDA in the next 30 days.

Calls to Swiss manufacturer Roche were not immediately returned Friday evening.