How To Prepare
Do not eat or drink anything (other than
water) for at least 8 hours before the test.
Many medicines may
affect the results of this test. Be sure to tell your doctor about
all the nonprescription and prescription medicines you take.
Talk
to your doctor about any concerns you have regarding the need for the test, its
risks, how it will be done, or what the results will mean. To help you
understand the importance of this test, fill out the
medical test information form
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