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 Causes of Delays in Drug Test Results

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.

Understanding Non-Negative Drug Test Results

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.

What Happens for DOT-Regulated Drug Tests?

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.

How Medical Prescriptions Affect Drug Test Results

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 how quickly the MRO reaches the donor.

The donor must provide a valid prescription to receive a negative result. When a potential safety concern arises, the MRO requests that the donor switch to a safer medication. Failure to make the change, or the inability to do so, leads the MRO to revise the result to “negative with a safety concern.”

Why the Process Takes Time

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