Blood test results can take up to a few weeks to receive, according to the National Heart, Lung and Blood Institute. Patients should follow up with their doctor to discuss test results.
Blood tests are common procedures that doctors use to check for diseases, treatment effectiveness and organ functions, states NIH. Medical professionals conduct blood tests using a needle or a finger prick to draw a small sample of blood. Laboratory workers use the whole blood to count the blood cells or separate blood cells from the plasma. Once the blood is separated, laboratory workers use the plasma to analyze the substances in the blood.