Amphetamines: an update on forensic issues.

Methamphetamine is currently enjoying a resurgence of popularity as a recreational drug. It presents a number of challenges to the forensic toxicologist both analytically and interpretively, and these latter interpretive issues are considered here. This review also discusses the current popular syntheses which account for the widespread domestic synthesis of the drug; the demographics of methamphetamine use in the United States as assessed from the Drug Abuse Warning Network (DAWN) data; developments in research of the neurotransporter pharmacology of the drug and its implications for interpretive forensic toxicology; the psychomotor effects of the drug and its potential for cognitive and functional impairment; interpretive issues related to postmortem blood drug concentrations and how these are impacted by evidence for incomplete distribution and the potential for postmortem redistribution; and, finally, concerns caused by designer methamphetamine analogues. All data indicate that methamphetamine and its analogues will present significant interpretive challenges to forensic toxicologists as the popularity of the drug continues to grow.