News Briefs

Reports of deaths related to drug-device interaction

According to the "FDA Drug Safety Newsletter Volume 1, Number 4

Summer 2008," health care professionals need to be alert to a dangerous drug-device interaction of icodextrin (Extraneal®) and point-of-care glucose monitoring. The report says the following:

FDA continues to receive reports of adverse events, including fatalities, related to a drug-device interaction associated with the use of icodextrin, a peritoneal dialysis solution, and certain point-of-care glucose monitoring devices that do not use a glucose-specific test strip. Icodextrin is broken down into maltose in vivo. Some test strips used with portable glucose meters cannot differentiate between maltose, glucose, and other sugars as they use methods that are not glucose-specific. The test strips associated with this drug-device interaction use glucose dehydrogenase pyrroloquinolinequinone (GDH-PQQ) or glucose-dye-oxidoreductase (GDO) as reagents. Examples of meters currently using these types of test strips include the Accu-Chek® (manufactured by Roche) and FreeStyle Navigator® (manufactured by Abbott) models. Health care providers and patients should refer to test strip package inserts or to consult the glucose monitoring device and test strip manufacturer(s) to confirm the glucose methodology in any system that is to be used for monitoring patients receiving icodextrin. A list of toll-free numbers for glucose monitor and test strip manufacturers is available at the Baxter Renal Clinical Help Line (1-888-RENAL-HELP).

Due to the presence of maltose in the blood of a patient receiving icodextrin therapy, the use of test strips that are not glucose-specific provides falsely elevated glucose readings. Falsely elevated blood glucose readings may lead to inappropriate insulin administration, which has caused hypoglycemia, coma, and death. Additionally, cases of true hypoglycemia can go untreated if masked by falsely elevated glucose readings.

As indicated in the Warning section of icodextrin's label, blood glucose measurement in patients receiving icodextrin must be done with a glucose-specific method (monitor and test strips) to avoid interference by maltose released from icodextrin. Glucose-specific methods (i.e., methods that are not affected by this interaction) include those that use glucose oxidase, glucose hexokinase, glucose dehydrogenase nicotine adenine dinucleotide (GDH-NAD), or flavin adenine dinucleotide glucose dehydrogenase (FAD-GDH) based reagents.

This drug-device interaction was identified prior to approval of icodextrin and it is described in product labeling. Several safety measures, including patient/health care professional education, have been undertaken by the manufacturer. Because FDA continues to receive reports of this adverse event, we are highlighting this drug-device interaction in additional FDA communications to the public. For a complete discussion on this drug-device interaction, including detailed case reports, see the recent FDA communiqué in the Institute for Safe Medication Practices' publication Medication Safety Alert.