FDA issues alert about glucose monitoring test strips and meters

Not all glucose meters and test strips use the GDH-PQQ method and only those that do are included in the FDA notification. (Other methods include glucose dehydrogenase nicotine adenine dinucleotide (GDH-NAD), glucose oxidase, glucose dehydrogenase flavin adenine dinucleotide (GDH-FAD), and hexokinase.) For a list of glucose meters and test strips that use GDH-PQQ methodology, click here.

Test strips and testing meters that use the GDH-PQQ method erroneously measure other types of sugars such as maltose, xylose, and galactose in addition to glucose. These non-glucose sugars are found in certain drugs and other preparations given to some patients as treatment. Since GDH-PQQ test strips measure other sugars in addition to glucose, they can give falsely elevated results. If action is taken in response to the results, such as administering more insulin, then hypoglycemia and, rarely, coma and death may result. The FDA has received reports of 13 deaths in the years 1997-2009 where it was documented that interference from other sugars resulted in falsely elevated results from tests using GDH-PQQ methodology.

Glucose meters and test strips are often used to measure glucose levels at patients' bedsides — referred to as "point of care testing" (POCT)— and for self-monitoring by diabetics. Tests for glucose that are performed in clinical laboratories do not use the GDH-PQQ method and are not affected by sugars other than glucose.

In the notification, the FDA cautions health care practitioners that GDH-PQQ test strips not be used to monitor the glucose levels of patients receiving drugs and other therapies containing non-glucose sugars. These patients should be monitored with tests performed in clinical laboratories or with other meters that do not use GDH-PQQ methodology. Some of the therapies in this category include icodextrin, a sugar used in some peritoneal dialysis solutions, and maltose, used in some immunoglobulin preparations. Because these medications are administered through a vein (intravenously) or are part of a same-day medical procedure, they typically are given in an inpatient or clinic setting. For a more complete list of these therapies and for additional details about the issue see: FDA Public Health Notification: Potentially Fatal Errors with GDH-PQQ Glucose Monitoring Technology.

The FDA urges diabetic patients and their caregivers to talk to their health care providers about drug therapies they are receiving and to know what type of test strips or meter they use. This may be done by checking the instructions that accompany the test strips or the glucose meter's packaging. Read more about the recommendations at: FDA Advice for Patients: Serious Errors with Certain Blood Glucose Meters and Strips.

Perone, M., Associated Press: FDA warns of faulty results with blood sugar tests. Available online at http://www.google.com/hostednews/ap/article/ALeqM5g7MCJhpzPfUsLbMOZ1-7LsrIbChwD9A2TUAG3 through http://www.google.com. Accessed August 19, 2009.

(August 13, 2009) FDA Public Health Notification: Potentially Fatal Errors with GDH-PQQ* Glucose Monitoring Technology. Available online at http://www.fda.gov/MedicalDevices/Safety/AlertsandNotices/PublicHealthNotifications/ucm176992.htm#attachment through http://www.fda.gov. Accessed August 19, 2009.

(August 13, 2009) Advice for Patients: Serious Errors with Certain Blood Glucose Monitoring Test Strips. Available online at http://www.fda.gov/MedicalDevices/Safety/AlertsandNotices/PatientAlerts/ucm177189.htm through http://www.fda.gov. Accessed August 19, 2009.