Blood Specimen Testing

Blood Testing – Drugs & Alcohol 

Blood as a specimen type for drug testing and alcohol testing can be utilized, but this is rare particularly for workplace drug testing.  One exception is in the State of Florida, a blood alcohol test is required under the State Drug Free Workplace Program for alcohol testing.  For Non-DOT testing a blood alcohol test could be acceptable but check State laws for any restrictions. 

Blood Specimen on Centrifuge

Blood testing for drugs or alcohol is not allowed at all for DOT drug & alcohol testing programs.  There is one exception in 49 CFR Part 40 when a valid test cannot be produced, and a negative result is required.  The MRO must determine if there is clinical evidence that the individual is currently an illicit drug user.  An MRO or the physician conducting an evaluation may conduct an alternative test (e.g., blood) as part of the medically appropriate procedures in determining clinical evidence of drug use.

Blood Testing for Drugs 

Often customers ask for a blood drug test thinking that the use of blood as the specimen is the most accurate.  This is not necessarily true.  Accurate drug tests are available using urine, hair, and oral fluid specimens.  The more important question to ask about drug testing is what you are trying to accomplish.  The various specimens available have different detection times which should be taken into consideration.

A blood test is invasive and expensive.  There is a short window of detection which can also be accomplished with the use of an oral fluid specimen.  Blood drug testing is very rare because of its cost and invasiveness.

Where are Blood Tests Commonly Used?

DUI cases are where we see blood testing for alcohol or perhaps other illicit drugs.  Law enforcement is trying to determine if the individual is currently impaired.  Also, in cases where cheating on the drug test is apparent, a situation might require a blood test because it is extremely difficult to adulterate or substitute this specimen.  The downside is that after 24 hours you will not detect alcohol or illicit drugs in blood.

Are Blood Drug Tests Available?

Our laboratories Quest Diagnostics and LabCorp do offer blood drug testing.  Again, be aware that blood testing for drugs may detect drug usage within minutes to several hours, depending on the drug use and dosage.  A urine drug test will give a longer look back period of up to 5 – 7 days for some drugs.  The blood drug or alcohol test is mostly used when you are trying to determine if the person is currently impaired or used the drugs or alcohol a short time ago.  If you would like to talk about ordering a blood drug test or perhaps a urine drug test – Call (866) 843-4545.

Woman holding blood samples in a vial

False Positives with Blood Drug Testing

Similar to drug testing with other specimens – urine, oral fluid, or hair; false positives can occur when the drug testing process is not done correctly.  Performing drug testing properly means that the following occurs:

Recommendation for Employment Drug Testing

For employment drug testing particularly pre-employment and random testing, urine drug testing is highly recommended.  Oral fluid specimens may be a good choice for post-accident or reasonable suspicion testing.  Blood testing is never recommended for employment testing as it is very invasive and very expensive.  Online orders for drug testing always available from National Drug Screening.