how long does it take a person drug test to come back
Blood tests are the least used for pre-employment drug screens because drugs are non-detectable in the blood stream after 48 hours. Labs generally report blood test results as quickly as they report urine test results.For most labs, that means results are available 24 hours after the specimen is tested, or 48 hours or more when the specimen must be delivered to a lab.hen drug screens return a negative result, the applicant is not tested again. The results of a negative test are usually available to employers within three business days after testing is completed. A positive test generally requires additional testing, and will thus take more time.