When urine or other matrices are not ideal, Labcorp offers drug testing of blood specimens.
Blood analysis may be appropriate in situations when it is suspected that a person is actively under the influence of drugs or alcohol. Since drugs are rapidly metabolized and eliminated from the body, blood analysis offers a very brief detection window. Drugs in blood are typically detectable within minutes to hours, depending on the drug and the dose, versus one to several days in urine.
Blood drug screen tests are performed on whole blood specimens using immunoassay screening with reflex to definitive testing.
To set up a blood drug testing program, contact Labcorp sales.
Available Blood Drug Tests
- Cocaine and metabolite
- THC (marijuana) metabolite
Recommended collection procedures for blood drug tests:
- Venipuncture, draw 2 gray-top tubes (preservative in the gray top tubes is essential for cocaine analysis)
- Mix specimen tubes by inversion
- Seal stoppers with tamper-evident tape (available on the chain of custody form)
- Label the tubes with specimen identification and/or patient information, ask donor to initial and date (if possible)
- Use chain of custody protocol, and document transfers on the chain of custody form
- Mark or write the desired test number(s) on the form
- Refrigerate if delay in shipment to lab is anticipated (>2 days). Do not freeze.