Oral fluid drug tests: effects of adulterants and foodstuffs.

An on-site oral fluid drug screen, Oratect, was used to investigate the effects of adulterants and foodstuffs on oral fluid test results. Common foods, beverages, food ingredients, cosmetics and hygienic products were demonstrated not to cause false positive results when tested 30 min after their consumption. Evaluations of two commercial oral fluid adulterants, "Clear Choice Fizzy Flush" and "Test'in Spit n Kleen Mouthwash" suggest their mechanism of action is the clearing of residual drugs of abuse compounds through rinsing of the oral cavity. They do not directly destroy the drug compounds or change the pH of the oral fluid. It is also suggested that a common mouthwash would perform similar action.