What happens during a creatinine test?Creatinine can be tested in blood or urine.For a creatinine blood test:A health care professional will take a blood sample from a vein in your arm, using a small needle. After the needle is inserted, a small amount of blood will be collected into a test tube or vial. You may feel a little sting when the needle goes in or out. This usually takes less than five minutes.For a creatinine urine test:Your health care provider will ask you to collect all urine during a 24-hour period. Your health care provider or a laboratory professional will give you a container to collect your urine and instructions on how to collect and store your samples. A 24-hour urine sample test generally includes the following steps:Empty your bladder in the morning and flush that urine away. Record the time.For the next 24 hours, save all your urine passed in the container provided.Store your urine container in the refrigerator or a cooler with ice.Return the sample container to your health provider's office or the laboratory as instructed.
