fasting specimen

fasting specimen

Lab medicine A blood specimen drawn from a Pt who has not eaten for 12 hrs; fasting is an absolute requirement for a limited number of tests–eg, GTT; prolonged fasting causes a marked–240% ↑ in bilirubin, ↑ plasma TGs, glycerol and free fatty acids, and a marked–± 50% ↓ in glucose. See Glucose tolerance test.