Ketones, Urine (Qualitative or Semiquantitative Measurement)

What Are Ketones?

Ketones are chemicals your liver produces when your cells do not get enough glucose (sugar) for energy and start burning fat instead. Small amounts can be normal during fasting, strenuous exercise, or a low-carbohydrate diet. Higher levels can build up in the blood and spill into the urine, which is what a urine ketone test detects.

Why the Test Is Done

Your healthcare provider may order a urine ketone test to monitor diabetes, especially when blood sugar is high or you are sick, or to look into symptoms such as nausea, vomiting, abdominal pain, confusion, or fruity-smelling breath. It can also be part of evaluating unexplained weight loss or a suspected metabolic problem.

How the Sample Is Collected

This test uses a urine sample, usually collected at home or in a clinic by urinating into a clean cup. In some cases a dipstick is briefly placed in the stream of urine or in a collected sample. No special preparation is usually needed, though your provider may give specific instructions.

What the Results Mean

A negative result means little or no ketone is detected. A positive result means ketones are present, and higher readings suggest more ketones. Results are usually reported as negative, trace, small, moderate, or large, but interpretation depends on your situation, so discuss the result with your provider rather than acting on it alone.