A patient fasting for blood tests may have water during his fast, according to Quest Diagnostics. It is advisable to drink a lot of water during the fast because it is harder for care providers to draw a patient's blood ... More »

The most common blood test, the complete blood count, or CBC, measures red blood cells, white blood cells, hemoglobin, hematocrit, platelets and mean corpuscular volume of the blood, according to the National Heart, Lung... More »

Metabolic profiles often require fasting, according to Adams Memorial Hospital. Other fasting blood tests include glucose testing, the renal function panel, and the lipid profile. When fasting for these tests, patients a... More »

Before a fasting blood test, a patient may only consume water and must abstain from any other foods or liquids, according to Quest Diagnostics. Fasting is necessary before certain blood tests in order to obtain accurate ... More »

Blood glucose tests and cholesterol tests require patients to avoid eating or drinking anything except water for 8 hours before the test, unless directed otherwise by a doctor, as stated by Geisinger Medical Laboratories... More »

A Chem 14 blood test, also called a comprehensive metabolic panel, is a group of 14 tests used to check organ function and monitor certain health conditions. A Chem 14 measures blood levels of sodium, potassium, chloride... More »

Numerous blood tests require fasting for up to 12 hours before the test, including lipid profile, renal function panel, glucose level, chem 7, basic metabolic profile, comprehensive metabolic profile and vitamin B-12, sa... More »