N,N-dimethyl-2-phenylpropan-1-amine quantification in urine: application to excretion study following single oral dietary supplement dose.

N,N-dimethyl-2-phenylpropan-1-amine (NN-DMPPA) is a new designer stimulant prohibited in sport in-competition according to the List of Prohibited Substances and Methods published by the World Anti-Doping Agency (WADA). The first published data on the excretion study of NN-DMPPA to support the knowledge of NN-DMPPA in routine anti-doping control have been presented. The reliable gas chromatography-mass spectrometry quantitative method (GC-MS) has been validated and applied to the excretion study of NN-DMPPA. The validation parameters of the GC-MS method for determination of NN-DMPPA in human urine were the linear calibration range of 100 to 7500 ng/mL, the LOD of 13.9 ng/mL and the LOQ of 42.2 ng/mL. According to the obtained repeatability, intermediate precision, and trueness, the applied GC-MS method was precise and accurate. Urine samples from three volunteers in the excretion study were collected for 5 days after single oral administration of the supplement NOXPUMP containing NN-DMPPA. The obtained results showed the maximum concentration of NN-DMPPA (189-303 ng/mL) in urine samples at a time of 2-3 h post-administration. The NN-DMPPA concentration in urine samples was higher than 50 ng/mL until 22-23 h after the dietary supplement ingestion. This means that according to the WADA rules the use of a supplement containing NN-DMPPA may be related to a positive case when athletes took this supplement in-competition. Moreover, excretion results demonstrate also that NN-DMPPA may be detected in urine samples by the applied GC-MS method till 46 h after supplement administration. Additionally, the excretion study of ß-methylphenethylamine as the second prohibited substance present in the supplement NOXPUMP has been investigated. Graphical Abstract Excretion study of new designer stimulant, N,N-dimethyl-2-phenylpropan-1-amine, and ß-methylphenethylamine following single oral NOXPUMP supplement dose.

Metabolic fate, mass spectral fragmentation, detectability, and differentiation in urine of the benzofuran designer drugs 6-APB and 6-MAPB in comparison to their 5-isomers using GC-MS and LC-(HR)-MS(n) techniques.

The number of so-called new psychoactive substances (NPS) is still increasing by modification of the chemical structure of known (scheduled) drugs. As analogues of amphetamines, 2-aminopropyl-benzofurans were sold. They were consumed because of their euphoric and empathogenic effects. After the 5-(2-aminopropyl)benzofurans, the 6-(2-aminopropyl)benzofuran isomers appeared. Thus, the question arose whether the metabolic fate, the mass spectral fragmentation, and the detectability in urine are comparable or different and how an intake can be differentiated. In the present study, 6-(2-aminopropyl)benzofuran (6-APB) and its N-methyl derivative 6-MAPB (N-methyl-6-(2-aminopropyl)benzofuran) were investigated to answer these questions. The metabolites of both drugs were identified in rat urine and human liver preparations using GC-MS and/or liquid chromatography-high resolution-mass spectrometry (LC-HR-MS(n)). Besides the parent drug, the main metabolite of 6-APB was 4-carboxymethyl-3-hydroxy amphetamine and the main metabolites of 6-MAPB were 6-APB (N-demethyl metabolite) and 4-carboxymethyl-3-hydroxy methamphetamine. The cytochrome P450 (CYP) isoenzymes involved in the 6-MAPB N-demethylation were CYP1A2, CYP2D6, and CYP3A4. An intake of a common users' dose of 6-APB or 6-MAPB could be confirmed in rat urine using the authors' GC-MS and the LC-MS(n) standard urine screening approaches with the corresponding parent drugs as major target allowing their differentiation. Furthermore, a differentiation of 6-APB and 6-MAPB in urine from their positional isomers 5-APB and 5-MAPB was successfully performed after solid phase extraction and heptafluorobutyrylation by GC-MS via their retention times.

Simultaneous quantification of atomoxetine as well as its primary oxidative and O-glucuronide metabolites in human plasma and urine using liquid chromatography tandem mass spectrometry (LC/MS/MS).

A sensitive and selective liquid chromatography tandem mass spectrometry (LC/MS/MS) method for the determination of atomoxetine and its metabolites (4-hydroxyatomoxetine, N-des-methylatomoxetine, and 4-hydroxyatomoxetine-O-glucuronide) has been developed for human plasma and urine. Using stable-labeled internal standards, the method proved to be accurate and precise for the analytes in all species, resulting in inter-batch accuracy (percent relative error, %RE) within 100+/-13% and inter-batch precision (relative standard deviation, %RSD) within 11%. Stability was demonstrated for the analytes in neat solutions and the reconstitution solvent, as well as plasma and urine (with or without the deconjugation reagent). The method was simple, robust (utilized for the analysis of several hundred clinical study samples), and amenable to high sample throughput.

N,N-dimethyl-2-phenylpropan-1-amine - new designer agent found in athlete urine and nutritional supplement.

Reports of new designer agents banned in sport being detected in supplements widely available for athletes are constantly emerging. The task of anti-doping laboratories is to control athletes for the presence of substances listed by the World Anti-Doping Agency (WADA) and those that are structurally/biologically similar to them. Recently, a new designer stimulant, N,N-dimethyl-2-phenylpropan-1-amine (NN-DMPPA), was detected by the WADA accredited anti-doping laboratory in Warsaw during routine anti-doping control. The urine samples from four athletes were analyzed in the screening method for stimulants and narcotics and the presence of NN-DMPPA was detected. The identity of NN-DMPPA was confirmed by gas chromatography-mass spectrometry using a synthesized reference standard. The measured concentrations of NN-DMPPA were between 0.51 and 6.51 µg/mL. The presence of the NN-DMPPA compound has been detected in the 'nutritional supplement' NOXPUMP that had been purchased in a store in Poland. NN-DMPPA at 121.7 µg/g was indicated in the investigated supplement together with another banned stimulant ß-methylphenethylamine. The presence of this new stimulant was not indicated on the labelling of the supplement, a situation which is not unusual within this market. Thus, it is important to make athletes aware of the risk related to the use of supplements. Moreover, specific legistation dealing with the commercialization of drugs banned for sport should be undertaken.

Effect of hepatic impairment on the pharmacokinetics of atomoxetine and its metabolites.

BACKGROUND AND OBJECTIVES: Atomoxetine is a treatment for attention-deficit/hyperactivity disorder and is primarily eliminated via cytochrome P4502D6 (CYP2D6). The pharmacokinetics of atomoxetine and its primary metabolites were investigated in 10 adults with hepatic impairment (6 moderate, 4 severe) and 10 age- and sex-matched control subjects, all being genotyped as CYP2D6 extensive metabolizers. METHODS: A single oral 20-mg dose of atomoxetine was given. Multiple blood samples were collected for 48 hours in healthy subjects and for 120 hours in patients. Urine was collected up to 24 hours. Before atomoxetine administration (10-20 days), sorbitol clearance and debrisoquin (INN, debrisoquine) metabolic ratio were determined as markers of hepatic blood flow and CYP2D6 activity, respectively. RESULTS: The systemic clearance of atomoxetine was significantly reduced in those with hepatic impairment compared with controls, thereby resulting in increased exposure (area under the concentration-time curve from time 0 to infinity, 1.58 versus 0.85 microg. h(-1). mL(-1); P =.035) but no change in maximum concentration. Mean 4-hydroxyatomoxetine area under the concentration-time curve from time 0 to time t and maximum concentration were increased approximately 7-fold and 2-fold, respectively (P =.0001 and P =.0056, respectively). For the glucuronide conjugate of 4-hydroxyatomoxetine, the mean half-life was longer and the mean area under the concentration-time curve from time 0 to infinity and the maximum concentration were lower (P =.0028, P =.003, and P =.0001, respectively). The sorbitol clearance was lower and the debrisoquin metabolic ratio was higher, reflecting reduced hepatic blood flow and decreased CYP2D6 activity, respectively. Decreased atomoxetine clearance in patients with hepatic impairment was clearly correlated with decreased CYP2D6 activity and decreased hepatic blood flow. Mean atomoxetine plasma protein binding was lower in patients with hepatic impairment compared with controls (96.5% versus 98.7%, P =.0008). Atomoxetine was well tolerated in the 2 populations. CONCLUSION: For patients with attention-deficit/hyperactivity disorder who have hepatic impairment, dosage adjustment is recommended. Initial target doses should be reduced to 25% and 50% of the normal dose for patients with severe and moderate hepatic impairment, respectively.

The identification and analysis of mexiletine and its metabolic products in man.

Sensitive and specific gas-liquid chromatographic methods were developed for the analysis of mexiletine and its metabolites in urine of man. The identity of the g.l.c. peaks was established by mass-spectrometry. The hydroxylamine (Va) was qualitatively identified and determined quantitatively after conversion to the more stable oxime (Vb). Selective extraction procedures, t.l.c. and derivatization with hexamethyldisilazane (HMDS) and trifluoroacetic anhydride (TFA) were used in the qualitative identification of the major metabolites (VI-IX), particularly in distinguishing the basic products VI and VII from their corresponding alcoholic products VIII and IX. The limit of detection of the g.l.c. method was 6 to 12 ng ml-1 for compounds I-IV, and 40 to 50 ng ml-1 for compounds Vb-IX.

Acute psychosis associated with recreational use of benzofuran 6-(2-aminopropyl)benzofuran (6-APB) and cannabis.

INTRODUCTION: There is evidence from around Europe of the availability and use of 6-(2-aminopropyl)benzofuran (6-APB) as a recreational drug. However, there is currently limited information on the acute toxicity of this compound. We describe here a case of acute toxicity associated with recreational use of legal high (6-APB) and cannabis, in which the comprehensive toxicological analysis confirmed the presence of a significant amount of 6-APB together with metabolites of both tetrahydrocannabinol and the synthetic cannabinoid receptor agonist (JWH-122). CASE REPORT: A 21-year-old gentleman with no previous medical and psychiatric history was brought to the emergency department (ED) after he had developed agitation and paranoid behaviour following the use of 6-APB purchased over the Internet. There was no obvious medical cause for his acute psychosis. He required diazepam to control his agitation and was subsequently transferred to a psychiatric hospital for ongoing management of his psychosis. Toxicological screening of a urine sample collected after presentation to the ED detected 6-APB, with an estimated urinary concentration of 2,000 ng/ml; other drugs were also detected, but at lower concentrations including metabolites of the synthetic cannabinoid receptor agonist JWH-122 and tetrahydrocannabinol. CONCLUSION: This is the first case of analytically confirmed acute toxicity associated with the detection of 6-APB which will provide some information on acute toxicity of this drug to help clinicians with the management of such patients and legislative authorities in their consideration for the need of its control.

Determination of atomoxetine and its metabolites in conventional and non-conventional biological matrices by liquid chromatography-tandem mass spectrometry.

A procedure based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) is described for determination of atomoxetine (ATX) and its metabolites 4-hydroxyatomoxetine (4-OH-ATX) and N-des-methylatomoxetine (N-des-ATX) in plasma, urine, oral fluid and sweat using duloxetine as internal standard. Analytes were extracted from 0.5 mL biological fluids and sweat patch with 2 mL aliquots of tert-butyl methyl ether. The organic layer was evaporated and redissolved in mobile phase. Chromatographic separation was carried out on reverse-phase column and an isocratic mobile phase formed by 40% water and 60% 5mM ammonium acetate, 47.2 mM formic acid, 4 mM trifluoroacetic acid in acetonitrile-water (85:15, v/v) at a flow rate of 0.5 mL/min. Separated analytes were identified and quantified by positive electrospray ionization tandem mass spectrometry and in multiple reaction monitoring acquisition mode. Limits of quantifications for the three analytes were 0.5 ng/mL plasma and oral fluid, 10 ng/mL urine and 1 ng/patch using 0.5 mL biological fluids or one sweat-patch per assay. Calibration curves were linear over the calibration ranges with r²>0.99. At three concentrations spanning the linear dynamic range of the assay, mean recoveries in different biological matrices were always higher than 65%. This method was applied to therapeutic monitoring of ATX and its metabolites 4-OH-ATX and N-des-ATX in conventional and non-conventional biological matrices from individuals in drug treatment.

A drug toxicity death involving propylhexedrine and mitragynine.

A death involving abuse of propylhexedrine and mitragynine is reported. Propylhexedrine is a potent α-adrenergic sympathomimetic amine found in nasal decongestant inhalers. The decedent was found dead in his living quarters with no signs of physical trauma. Analysis of his computer showed information on kratom, a plant that contains mitragynine, which produces opiumlike effects at high doses and stimulant effects at low doses, and a procedure to concentrate propylhexedrine from over-the-counter inhalers. Toxicology results revealed the presence of 1.7 mg/L propylhexedrine and 0.39 mg/L mitragynine in his blood. Both drugs, as well as acetaminophen, morphine, and promethazine, were detected in the urine. Quantitative results were achieved by gas chromatography-mass spectrometry monitoring selected ions for the propylhexedrine heptafluorobutyryl derivative. Liquid chromatography-tandem mass spectrometry in multiple reactions monitoring mode was used to obtain quantitative results for mitragynine. The cause of death was ruled propylhexedrine toxicity, and the manner of death was ruled accidental. Mitragynine may have contributed as well, but as there are no published data for drug concentrations, the medical examiner did not include mitragynine toxicity in the cause of death. This is the first known publication of a case report involving propylhexedrine and mitragynine.

Selective determination of secondary amines as their N-diethylthiophosphoryl derivatives by gas chromatography with flame photometric detection.

A selective and sensitive method has been developed for the determination of secondary amines by gas chromatography (GC). After removal of primary amines by the reaction with o-phthaldialdehyde, secondary amines were converted into their N-diethylthiophosphoryl derivatives and then measured by GC with flame photometric detection using a DB-1701 capillary column. The derivatives were sufficiently volatile and stable to give single symmetrical peaks. The detection limits of secondary amines were ca. 0.05-0.2 pmol per injection. N-Methylcyclohexylamine was used as an internal standard. The calibration curves for secondary amines in the range 1-20 nmol were linear and sufficiently reproducible for quantitative determination. This method was successfully applied to small urine samples without prior clean-up. Overall recoveries of secondary amines added to urine samples were 91-105%. By using this method, secondary amines in urine samples could be analysed without any influence from primary amines and other coexisting substances. The analytical results of secondary amine content in urine samples of normal subjects are presented.

Disposition and metabolic fate of atomoxetine hydrochloride: pharmacokinetics, metabolism, and excretion in the Fischer 344 rat and beagle dog.

These studies were designed to characterize the disposition and metabolism of atomoxetine hydrochloride [(-)-N-methyl-gamma-(2-methylphenoxy)benzenepropanamine hydrochloride; formerly know as tomoxetine hydrochloride] in Fischer 344 rats and beagle dogs. Atomoxetine was well absorbed from the gastrointestinal tract and cleared primarily by metabolism with the majority of its metabolites being excreted into the urine, 66% of the total dose in the rat and 48% in the dog. Fecal excretion, 32% of the total dose in the rat and 42% in the dog, appears to be due to biliary elimination and not due to unabsorbed dose. Nearly the entire dose was excreted within 24 h in both species. In the rat, low oral bioavailability was observed (F = 4%) compared with the high oral bioavailability in dog (F = 74%). These differences appear to be almost purely mediated by the efficient first-pass hepatic clearance of atomoxetine in rat. The biotransformation of atomoxetine was similar in the rat and dog, undergoing aromatic ring hydroxylation, benzylic oxidation (rat only), and N-demethylation. The primary oxidative metabolite of atomoxetine was 4-hydroxyatomoxetine, which was subsequently conjugated forming O-glucuronide and O-sulfate (dog only) metabolites. Although subtle differences were observed in the excretion and biotransformation of atomoxetine in rats and dogs, the primary difference observed between these species was the extent of first-pass metabolism and the degree of systemic exposure to atomoxetine and its metabolites.

Disposition and metabolic fate of atomoxetine hydrochloride: the role of CYP2D6 in human disposition and metabolism.

The role of the polymorphic cytochrome p450 2D6 (CYP2D6) in the pharmacokinetics of atomoxetine hydrochloride [(-)-N-methyl-gamma-(2-methylphenoxy)benzenepropanamine hydrochloride; LY139603] has been documented following both single and multiple doses of the drug. In this study, the influence of the CYP2D6 polymorphism on the overall disposition and metabolism of a 20-mg dose of (14)C-atomoxetine was evaluated in CYP2D6 extensive metabolizer (EM; n = 4) and poor metabolizer (PM; n = 3) subjects under steady-state conditions. Atomoxetine was well absorbed from the gastrointestinal tract and cleared primarily by metabolism with the preponderance of radioactivity being excreted into the urine. In EM subjects, the majority of the radioactive dose was excreted within 24 h, whereas in PM subjects the majority of the dose was excreted by 72 h. The biotransformation of atomoxetine was similar in all subjects undergoing aromatic ring hydroxylation, benzylic oxidation, and N-demethylation with no CYP2D6 phenotype-specific metabolites. The primary oxidative metabolite of atomoxetine was 4-hydroxyatomoxetine, which was subsequently conjugated forming 4-hydroxyatomoxetine-O-glucuronide. Due to the absence of CYP2D6 activity, the systemic exposure to radioactivity was prolonged in PM subjects (t(1/2) = 62 h) compared with EM subjects (t(1/2) = 18 h). In EM subjects, atomoxetine (t(1/2) = 5 h) and 4-hydroxyatomoxetine-O-glucuronide (t(1/2) = 7 h) were the principle circulating species, whereas atomoxetine (t(1/2) = 20 h) and N-desmethylatomoxetine (t(1/2) = 33 h) were the principle circulating species in PM subjects. Although differences were observed in the excretion and relative amounts of metabolites formed, the primary difference observed between EM and PM subjects was the rate at which atomoxetine was biotransformed to 4-hydroxyatomoxetine.