How To Prepare
Do not do any strenuous exercise for 2 days (48 hours) before
having creatinine tests.
Do not eat more than
8 oz (227 g) of meat,
especially beef, or other protein for 24 hours before the blood creatinine test
and during the creatinine clearance urine test.
It is important to drink enough fluids during the 24-hour urine
collection but do not drink coffee and tea. These are
diuretics that cause your body to pass more
urine.