Request a copy of the test results and the chain-of-custody documentation
Confirm whether the initial test was a screening test or a confirmatory test
Ask for confirmatory testing if only a screening test was performed
Verify that the sample was properly collected, labeled, stored, and transported
Check for possible sample mix-up, contamination, or clerical error
Review any prescription medications, over-the-counter drugs, and supplements you used
Gather pharmacy records, prescriptions, and medical documentation
Request a retest of the original sample if it is still available
Ask for an independent laboratory retest if permitted
Document the date, time, location, and people involved in the test process
File a written dispute with the testing facility or employer as soon as possible
Follow the appeal or grievance procedure in the testing policy
Ask for the medical review officer to review legitimate medication explanations
Keep copies of all communications, reports, and supporting documents
Consult an attorney or union representative if the result affects employment or legal status