Chapter 14. Amphetamine-Like Designer Drugs Including Bath Salts: Few Assays and Many Unanswered Questions

Synthetic cathinones, as β-keto analogues within the broader family of β-phenethylamine amphetamine-type stimulants, have evolved through waves of structural modifications, enabling rapid adaptation to legislation and supply disruptions. Today they circulate in diverse retail forms (including the “bath salts” label) and are sometimes misrepresented as other stimulants, contributing to heterogeneous risk profiles across regions. Monitoring sources converge on sustained availability and periodic substitution by close analogues, while casework continues to encounter compounds with limited clinical and toxicological characterization. This chapter first sets the public-health and pharmaco-toxicological context, then details the analytical implications for clinical and forensic drug testing across blood/plasma, urine, oral fluid, hair and other matrices. Emphasis is placed on interpretive context (patterns of use, misrepresentation, co-exposures), on the practical impact of compound turnover and on stability and sampling formats, relevant to specimen handling. The goal is to provide an integrated understanding of how these drugs arise, circulate and are detected, informing proactive and adaptable testing practices as stimulant markets continue to shift.