Free Inositol/Creatinine Ratio, 5-Hour Urine — Post-Glucose Solution

What is this test?

This test measures free inositol, a sugar alcohol involved in cellular signaling, in a timed 5-hour urine collection. The result is divided by the urine creatinine level to help account for differences in urine concentration.

Why might I need this test?

It may be ordered to evaluate how the kidneys handle glucose and related substances after a glucose load, particularly in connection with an oral glucose tolerance evaluation. Your clinician will interpret it alongside blood glucose results, symptoms, medications, and pregnancy status when relevant.

How is the test performed?

After the prescribed glucose solution is given, all urine produced during the specified 5-hour period is collected and tested. The laboratory measures free inositol and creatinine and reports their ratio.

How do I prepare for the test?

Follow the exact instructions provided for the glucose solution and collection period. Record the start and end times, collect every urine sample in the container provided, and tell the laboratory if any sample is missed. Ask whether the container should be refrigerated and whether dietary or medication changes are needed.