Purina Discontinues ''Glucotest'' Feline Urinary Glucose Detection System

For the last few years, I've routinely used the Purina Glucotest urine glucose indicator packets to provide owners of diabetic cats with an easy means of monitoring their cat at home. This detection system added to the cat's litter provided a nice gauge of the degree of glucosuria at home in a non-invasive way. 

I have especially found the Glucotest granules helpful in telling me if there is any glucose in the urine after I've lowered or discontinued the insulin dose in a cat that I think is going into diabetic remission.  

The bad news is that I just found out from the company that they have discontinued the product and will no long make it. Can you recommend an alternate product that has a similar function?

My Response:

Purina Glucotest brand Feline Urinary Glucose Detection System gave cat owners a way to help monitor their diabetic cats at home. The indicator particles were mixed in with the litter and checked within a 12-hour period for a color change to indicate the level of glucose in your cat's urine (1).

Unfortunately, I don't know of an alternate product to replace the Glucotest. Obviously, we can still check urine glucose concentrations using a reagent strip (e.g., Diastix or KetoDiastix) (1-3).

However, the problem for many owners is how to collect the urine to test from their diabetic cats. I have had some luck with owners collecting urine using non-absorbable litter, such as No-Sorb or Kit4Cat hydrophobic litter and then using glucose reagent strips to test the litter.  Of these two non-absorbable litters, most cats prefer the Kit4Cat product since it looks and feels like regular sand; its hydrophobic sand keeps the cat’s urine on top, making sample collection easy (see box on right).  

Obviously, these non-aborbable litter products are also useful for collection of urine for any other purpose, including running a complete urinalysis.

That said, I do not recommend monitoring urine glucose concentrations to change the insulin dose in cats.  Monitoring of urine glucose is only a very indirect way to assess blood glucose concentrations, and results can be very misleading, especially when used as the sole monitoring method (1,2,4).  Remember that the results of a urine glucose concentration reflects the average blood glucose concentration over many hours, as urine is produced and high blood glucose concentrations exceed the renal threshold and is excreted into the urine.  Therefore, transient hypoglycemia or the Somogyi effect (prolonged rebound hyperglycemia following a profound decrease in circulating glucose concentrations) will be missed by urine glucose monitoring (2,4).

Over the last few years, it has become more common for owners to directly measure blood glucose at home, which has many advantages over urine glucose monitoring (4-7). In fact, many veterinarians now routinely recommend home glucose monitoring for their diabetic cats, which is particularly helpful if tight glucose regulation and diabetic remission is the goal. If this is not possible, use of a combination of clinical signs, determination of serum fructosamine concentrations, and periodic in-hospital glucose curves can be used for diabetic regulation (2,4).

This trend away from the use of urine glucose monitoring is probably one reason Purina Veterinary Diagnostics decided to stop making this Urinary Glucose Detection System.

References:

1. Fletcher JM, Behrend EN, Welles EG, et al. Glucose detection and concentration estimation in feline urine samples with the Bayer Multistix and Purina Glucotest. J Feline Med Surg 2011;13:705-711. 
2. Miller E. Long-term monitoring of the diabetic dog and cat. Clinical signs, serial blood glucose determinations, urine glucose, and glycated blood proteins. Vet Clin North Am Small Anim Pract 1995;25:571-584. 
3. Schaer M. A justification for urine glucose monitoring in the diabetic dog and cat. J Am Anim Hosp Assoc 2001;37:311-312. 
4. Cook AK. Monitoring methods for dogs and cats with diabetes mellitus. J Diabetes Sci Technol 2012;6:491-495. 
5. Reusch CE, Kley S, Casella M. Home monitoring of the diabetic cat. J Feline Med Surg 2006;8:119-127. 
6. Zeugswetter FK, Rebuzzi L, Karlovits S. Alternative sampling site for blood glucose testing in cats: giving the ears a rest. J Feline Med Surg 2010;12:710-713. 
7. Ford SL, Lynch H. Practical use of home blood glucose monitoring in feline diabetics. Vet Clin North Am Small Anim Pract 2013;43:283-301.