Diagnose of Diabetes
Doctors will send you for a routine check-up even when you are not a diabetic or even when you don't have any symptoms of diabetes. This check-up will include random blood sugar and urine test. This can be done any time of the day or night, it does not matter where you go or what you have eaten or drunk.
If the doctor sees some signs of you becoming diabetic in future, he will ask you to go for a test that is after dinner. You will be told not to eat anything or drink anything till next morning; no breakfast, coffee, and tea.
All tests must be conducted under absolutely normal conditions, not when you have just recovered from sickness, or when you have been in bed for long time or after a travel binge. The test results will not be correct.
A common mistake which even most educated people make is when they go for these tests before breakfast; they will not take the medication which they usually take, so the results will not be correct. Many doctors will not advise the patients about what medication to take and what not to take before they go for different diagnostic tests. As a matter of fact, all doctors and people at the diagnostic labs will re-check and ask you, 'Hope you have not taken anything, no coffee, no tea?'
Tests to detect the presence of sugar in the urine (glycosuria)
Tests to detect the amount of sugar in the blood.