As good as we are at responding to our clients’ requests, there are some things you cannot rush.

The majority of negative test results are delivered within 24-48 hours of collection.

Common delays include

  • delays in shipping from the collector because the specimen was collected overnight or on a weekend
  • errors in the paperwork submitted by the collector
  • sometimes issues with the specimen that require additional attention at the lab.

Also, not all drug tests are negative.

Here is how non-negative drug test results work.

If a drug tests positive on the initial screening test, then the lab performs a more thorough test (most commonly GC/MS), usually the following day. If it fails that test the result goes to the MRO for review.

Our MRO then contacts the donor to ask for explanation.

If the donor is contacted immediately and the MRO is able to get all the information s/he needs, the result is released. Total time can be as little as 3 or 4 business days.

For federally regulated (DOT) tests, our MRO tries to reach the donor 3 times within 24 hours. If the MRO is not able to contact the donor, the DOT Start Clock begins, and the employer is asked to help. If the MRO does not hear from the donor within the required 10 days, the result is released as a “non-contact positive.”

For non-DOT tests, the MRO tries to reach the donor once and give him/her 24 hours to respond. If no response, they release the result as a “non-contact positive.

Following a conversation between the MRO and the donor, if the donor has no satisfactory explanation for a positive result, the result is released as positive.

If there is an explanation (e.g. a prescription), then the MRO releases it as negative, sometimes with a safety concern letter.

Note that, as of this writing, marijuana is a Schedule I drug and cannot be legally prescribed. Many states have medical marijuana programs and users may provide a medical marijuana card to the MRO. Since the MRO has no way to verify the authenticity of such cards, so a positive result for THC will always be reported as a positive. For non-DOT testing, there will often be a note that the donor claimed medical marijuana use, but the MRO did not verify it. All federal (DOT) marijuana positives are reported as positive.

For DOT tests, the lab and MRO are not allowed to tell us anything until it’s complete.

DOT non-negatives can take anywhere from 2 days to more than two weeks, depending on whether the MRO can reach the donor right away. If a prescription is involved, the donor is given time to provide it.

If the donor provides a valid prescription, the MRO is required to release a negative result. If there is a possible safety concern, the MRO will ask that the donor be switched to a safer medication. If that is not done, or not possible, the MRO may revise the negative result to be “negative with a safety concern.”

We all wish the process were faster, but the system is designed to protect the donor’s privacy in the case of a prescription, and to protect the rest of us from liability in those cases as well.

Lastly, don’t assume a slow result will come back positive. Sometimes they come back negative. Wait till you know for sure.

Further Reading about Drug Tests: