Excretion Profile of 4-Methylthioamphetamine in Dogs

Abstract

4-Methylthioamphetamine (4-MTA) is a new drug of abuse, and owing to a number of deaths in the EU over a 2-year period, it has become a major cause for concern. Little is known about the metabolism, half-life or excretion pro®le of 4-MTA, in man. We used a canine model to study the excretion pro®le of 4-MTA.Urine samples were screened for 4-MTA with EMIT amphetamine immunoassay, followed by con®rmatory analysis using GC-MS. 4-MTA was detectable using EMITamphetamine immunoassay down to 1 mg mL À1 in drug-free urine samples to which 4-MTA was added. 4-MTA was detectable by EMIT up to 23 h after administration. Base extracted urine samples were subjected to¯ash derivatization using N-methylbis(tri¯uoroacetamide) and the resulting tri¯uoroacetylated compound yielded a well fragmented mass spectrum under the GC-MS conditions used. Quanti®cation of 4-MTA in the urine samples revealed 15, 11 and 20 mg mL À1 at 5Á5, 13Á5 and 23 h, respectively. 4-MTA is detectable by immunoassay at 1 mg mL À1 and can be detected in dogs up to 23 h after administration. EMIT positive screens can be checked using GC-MS incorporating derivatization to con®rm the presence of 4-MTA.

Simultaneous determination of amphetamine derivatives in human urine after SPE extraction and HPLC‐UV analysis

“…Concerning 2C-B and 4-MTA, the metabolic studies already published are scarce and, to our knowledge, non-existent for humans in a definitive form. Only a presumptive metabolic profile for 4-MTA in humans was published by Elliot (2001) and studies are in progress on the metabolism of 4-MTA in dog (Kavanagh et al, 1999). In an in vivo pharmacokinetic study in mice performed by our group, it was observed that 4-MTA is predominantly eliminated without biotransformation in accordance with the preliminary results of Kavanagh et al (1999), in the dog.…”

“…Only a presumptive metabolic profile for 4-MTA in humans was published by Elliot (2001) and studies are in progress on the metabolism of 4-MTA in dog (Kavanagh et al, 1999). In an in vivo pharmacokinetic study in mice performed by our group, it was observed that 4-MTA is predominantly eliminated without biotransformation in accordance with the preliminary results of Kavanagh et al (1999), in the dog. However, some 4-MTA metabolites were identified in the mouse urine extracts by gas chromatography with mass detection (GC-MS; Carmo et al, 2002).…”

“…Toxicokinetic studies of MDMA with characterization of phase I and phase II metabolites were carried out with GC-MS and HPLC-MS (Maurer et al, 2000). Immunoassay techniques have also been tried for the screening of 4-MTA (Kavanagh et al, 1999).…”

Phenylalkylamine abuse among opiate addicts attending a methadone treatment programme in the Republic of Ireland

“…However, King 18 It has been shown in the past that 4-MTA cross-reacts with the particular immunoassay system that was em ployed here. 19 The absence of 4-MTA was due probably to the limited number of seizures in Europe, coupled with the high incidence of 4-MTA associated fatality, 20 which may have led to a decline in its use. Although not particularly renowned for its abuse potential the appetite suppressant, phentermine, will rarely induce euphoria but can cause insomnia.…”