Drug abuse is a psychiatric disorder affecting approximately 16.7% of the American population, but a person abusing drugs also needs a job. People try to beat drug tests in various ways, from substituting someone else’s urine as their own, drinking flushing and detoxifying agents, and adding adulterants to the urine specimen after collection. In vitro urinary adulterants can vary from common household chemicals to Internet-based chemicals such as “Urine Aid”, “Urine Luck,” “Klear,” “Stealth,” and zinc sulfate. Criteria for workplace (also known as a legal drug test) are more stringent than medical drug tests performed in an emergency room or a doctor’s office. When tested positive in a workplace drug testing program, a person may come up with many excuses, such as taking prescription medication, drinking herbal tea, and passively inhaling marijuana. Therefore, a physician known as “Medical Review Officer” reviews the positive drug testing result confirmed by a mass spectrometric method (also known as analytical positive) to ensure that there is no alternative explanation for the positive test result. Professionals involved in workplace drug testing should be familiar with various ways people try to beat drug tests and defend positive results.