how long to fast for a blood test

A neat row of colored vacutainer collection tubes in a laboratory rack to illustrate if a patient needs to be fasting before blood draws.

Do You Have to Fast for a CBC? The Honest Answer

Fasting for a CBC isn't required—you can eat, drink, and take meds normally. The catch: other tests drawn with it may need an empty stomach.

✓ EDUCATIONAL

Written & edited by: Sameer Patel — Founder & Editor Calculators built on published formulas Educational information — not a substitute for medical advice