Production of ketone bodies is a normal response to a shortage of glucose, meant to provide an alternate source of fuel from fatty acids.

A strip consists of a thin piece of plastic film slightly larger than a matchstick, with a reagent pad on one end that is either dipped into a urine sample or passed through the stream while the user is voiding.

In severe diabetic ketoacidosis, the dipstix reaction based on sodium nitroprusside may underestimate the level of ketone bodies in the blood.

In addition, when diabetic treatment is being switched from insulin to oral hypoglycemic agents, the patient's urine should be monitored for ketonuria.

The development of ketonuria within 24 hours after insulin withdrawal usually indicates a poor response to the oral hypoglycemic agents.

Diabetic patients should have their urine tested regularly for glucose and ketones, particularly when acute infection or other illness develops.