Flash glucose monitors… do you use them?
Flash glucose monitors are helpful guides for diabetic dogs and cats. They can also be used in pets with insulinomas tracking low glucose events. BUT what about in healthy dogs? Here lies our conundrum - they need to be interpreted carefully with the patient information in hand :)
Journal Article
Evaluation of low and high interstitial glucose concentrations in healthy, nondiabetic dogs using a flash glucose monitoring system Open Access
Journal of Veterinary Internal Medicine, Volume 40, Issue 2, March-April 2026, aalag032, https://doi.org/10.1093/jvimsj/aalag032
Published:
06 March 2026
Abstract
Background
Flash glucose monitoring systems (FGMS; FreeStyle Libre) are useful devices for managing diabetic patients. The FGMS is reportedly accurate for diabetic dogs with hyperglycemia and euglycemia but might underestimate glucose concentrations during hypoglycemia.
Hypothesis/Objectives
Assess the frequency of low and high interstitial glucose (IG) concentrations recorded in healthy, nondiabetic dogs using FGMS.
Animals
Twenty-three hospital employee-owned dogs.
Methods
Prospective, observational study. The FGMS was placed on all dogs to record ≥488 readings each over up to 14 days. Interstitial glucose concentrations were analyzed to identify the frequency of low, normal, and high IG concentrations. Descriptive statistics were calculated, and comparisons between demographic cohorts were performed.
Results
During monitoring, 73.7% (14/19) of participants had at least one low IG concentration (<70 mg/dL), whereas 26.3% (5/19) had at least one high IG concentration (>180 mg/dL). The mean (±SD) percentage of low and high IG concentrations per dog was 2.8 ± 4.3% and 0.8 ± 2.2%, respectively. Markedly decreased IG (<55 mg/dL) and markedly increased (>250 mg/dL) IG concentrations occurred in 63.2% (12/19) and 10.5% (2/19) of dogs, respectively. The frequency of low IG concentrations in dogs weighing 2.5-20.5 kg (2.2%; interquartile range [IQR], 1.1-5.0) was higher (P = .02) than in dogs weighing 20.6-41.4 kg (0.1%; IQR, 0.0-0.7%); the median difference was 2.1% (95% confidence interval, 0.6-10.1).
Conclusions and clinical importance
Low and high IG concentrations were recorded in healthy, nondiabetic dogs, providing a context for interpreting FGMS results in diabetic dogs.
