Does a laboratory medicine perform blood test?

Laboratory medicine includes the scientific work behind many blood tests. A trained professional may confirm your identity, review the requested tests and take a small sample from a vein, commonly in the arm. The laboratory then separates and examines the sample using methods suited to the question being asked. Results can help assess blood cells, inflammation, hormones, organs, nutrients or infection. The laboratory usually sends the report to the clinician who requested it, because results need to be interpreted alongside your symptoms, examination and medical history.

Follow the instructions given with your appointment. Some tests require fasting, while others do not, so do not skip meals unless you were specifically told to. Tell the team about medicines, supplements, allergies, pregnancy or a tendency to faint. Wear clothing that allows easy access to your arm, drink water unless fluid restriction applies, and remain seated briefly after collection if you feel light-headed. You can review the general process in the Blood Test guide.

Contact the requesting clinician if a result is unclear, unexpectedly abnormal or has not arrived within the timeframe you were given. After collection, seek prompt medical help for bleeding that does not settle with firm pressure, increasing swelling, severe pain, spreading redness or fainting that does not quickly resolve. A blood test is one part of assessment and should not delay urgent care for chest pain, severe breathing difficulty, sudden weakness or confusion.

Ask which tests were ordered, whether preparation is needed, when and how results will be shared, and what you should do if the sample cannot be collected. You may also ask whether medicines or supplements could affect interpretation and whether a repeat sample is needed.