Drugs of Abuse: Analyses and Ingested Agents That Can Induce Interference or Cross-Reactivity

Drug abuse is rampant in society having a detrimental effect towards public safety and productivity in industry. Therefore, testing for drugs of abuse is paramount, and those analytical procedures employed are evolving in sophistication, specificity, and sensitivity. However, the quandary still exists regarding the interference and/or cross-reactivity of ingested foods/drugs, thereby contributing to false positive/negative results. Typically, an initial drug screen involves the utilization of an immunoassay due to its feasibility and low cost; unfortunately, it is this very assay that appears to be interfered with the most. False results from these initial screens can have serious implications towards a person's employment and leave a lasting stigma. This review attempts to highlight those analytical procedures used to screen for drugs of abuse along with listing those ingested foods/drugs that can potentially interfere with those analytical methods.