Drug use among truck drivers across the globe has often been associated with several common factors, all of which are present in the United States. In a study published by Occupational and Environmental Medicine, the factors most closely tied to drug use by truck drivers include longer trips, isolation, sleep deprivation, desire for higher income, inexperience, driving at night, alcohol use, trucking for smaller companies, earnings based on production and where actual income is below expected income. The substances most commonly studied in connection with truck drivers include alcohol, marijuana, cocaine and amphetamines. The study reported that amphetamine use worldwide was mostly commonly associated with poor working conditions.

In the United States, the rules regulating the manner and methods for drug and alcohol testing of Commercial Driver Licensed (CDL) employees are located in part 40, title 49 of the Code of Federal Regulations. According to the Federal Motor Carrier Safety Administration of the Department of Transportation, CDL drivers must submit to drug testing when required. Along with alcohol, DOT requires testing for five classes of drugs: marijuana, amphetamines and methamphetamines, opiates, PCP and cocaine. Testing is required for all new CDL drivers. It is also required on a random basis or upon reasonable suspicion by a supervisor. When an accident occurs involving a fatality, injury, or major vehicle damage, CDL drivers must submit to alcohol testing with 8 hours and drug testing within 32 hours. These tests are kept and recorded according to regulation so that follow-up testing can occur.

If a CDL driver tests positive for one of these tests, or refuses to be tested, he or she is prohibited from operating on public highways. The driver is then required to submit to a “return-to-duty” process. Upon completion, and before a driver can begin operating again, additional testing is required.