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PubMed2006

Analysis of the impurities in the methamphetamine synthesized by three different methods from ephedrine and pseudoephedrine.

Organic impurities of methamphetamine may show different patterns by synthesis. In the present study, we tried to find the impurities reflecting the conditions of synthesis by comparing impurity patterns of the methamphetamine samples synthesized by different methods. Sixteen methamphetamine samples were synthesized from ephedrine and pseudoephedrine by the three different manufacturing methods of Emde, Nagai and Moscow. The synthesized samples were extracted with ethyl acetate containing four internal standards, and the patterns of the organic impurities were investigated by GC-MS and GC-FID . Through the investigation, we found 10 peaks appearing in the latter part of GC chromatograms are characteristic to synthesis. The areas of the selected peaks were converted to the variables suitable for the statistical calculation, and the synthesized samples could be classified into four groups through the resultant cluster analysis.

Journal Article↗

PubMed2006

Capillary electrophoretic analysis of phosphorus species in clandestine methamphetamine laboratory samples.

The clandestine manufacture of methamphetamine is a spreading epidemic. Manufacturing methods are constantly changing, necessitating the implementation of new analytical tools to identify materials from these labs. Characterization of phosphate, phosphite, and hypophosphite ions is necessary to distinguish the various phosphorus-iodine manufacturing methods that are popular methods for reducing pseudoephedrine to methamphetamine. This work describes a capillary electrophoresis method to separate acetate, azide, bromide, carbonate, chlorate, chloride, chromate, fluoride, hypophosphite, iodide, nitrate, nitrite, perchlorate, phosphate, phosphite, sulfate, sulfite, and thiocyanate. The CElixerOA 8.2 dynamic coating system was modified by lowering the capillary temperature to 15 degrees C and using an acid flush between runs to remove adsorbed materials. This allows detection of ions down to between 10 and 30 parts per million with percent relative standard deviations of normalized migration times under 0.1%. This method is a valuable tool for the characterization of phosphate, phosphite, and hypophosphite in routine analysis of clandestine methamphetamine manufacturing evidence and has a broader application in other areas of forensic analysis.

Journal Article↗

PubMed2006

Contingency management for the treatment of methamphetamine use disorders.

OBJECTIVE: Theory and some preliminary evidence suggest that contingency management may be an effective treatment strategy or adjunct to psychosocial treatment for methamphetamine use disorders. An experimentally rigorous investigation on the topic was provided by a large multisite trial conducted under the auspices of the Clinical Trials Network of the National Institute on Drug Abuse. METHOD: The authors report data on 113 participants who were diagnosed with methamphetamine abuse or dependence. They were randomly assigned to receive 12 weeks of either treatment as usual or treatment as usual plus contingency management. Urine samples were tested for illicit drugs, and breath samples were tested for alcohol. The reinforcers for drug-negative samples were plastic chips, some of which could be exchanged for prizes. The number of plastic chips drawn increased with each week of negative samples but was reset to one after a missed or positive sample. RESULTS: The participants in both groups remained in treatment for equivalent times, but those receiving contingency management in addition to usual treatment submitted significantly more negative samples, and they were abstinent for a longer period of time (5 versus 3 weeks). CONCLUSIONS: These results suggest that contingency management has promise as a component in treatment strategies for methamphetamine use disorder.

Adult↗

PubMed2001

Use of dynamically coated capillaries for the routine analysis of methamphetamine, amphetamine, MDA, MDMA, MDEA, and cocaine using capillary electrophoresis.

A rapid, accurate, precise, reproducible, economical, and environmentally gentle method using capillary electrophoresis (CE) is presented for the routine analysis of methamphetamine, amphetamine, MDA, MDMA, MDEA, and cocaine in seized drugs. The methodology uses a 32 cm by 50 microm capillary (length to detector 23.5 cm) with a commercially available buffer kit and diode array UV detection. Dynamic coating of the capillary surface is accomplished by flushing with base for 1 min, a proprietary polycation for 1 min, and then a proprietary polyanion for 2 min. This approach provides a relatively high and stable electroosmotic flow (EOF), even at low pHs. The background electrolyte (BGE) contains 75 mM phosphate buffer (pH 2.5) with the same polyanion as above. Using this methodology, amphetamine, methamphetamine, MDA, MDMA, MDEA, and an internal standard (n-butylamphetamine) are baseline resolved in less than 5 min. The run-to-run migration time %RSDs and peak area %RSDs are typically <0.3% and <2.1%, respectively. The day-to-day and capillary-to-capillary migration time %RSDs are <1.5% and <2.1%, respectively. The %RSDs of the relative migration times compared with the internal standard on a day-to-day and capillary-to-capillary basis are <0.2% and <0.06%, respectively. The linear dynamic range using peak areas range from 0.003 to 0.10 mg/mL. The correlation coefficients are >0.9998, with all calibration curves passing at or near the origin. Similar data are obtained for cocaine and its internal standard henyltoloxamine. None of the compounds usually encountered in illicit samples interfere with the target compound (e.g., methamphetamine and cocaine) or the internal standard. Quantitative results for synthetic mixtures and seized exhibits are in good agreement with actual values, and also with results obtained from other techniques. The relatively high EOF for the dynamically coated capillary system allows for the screening of basic, acidic, and neutral adulterants in drug seizures; identification is facilitated by the use of automated UV library searches.

Journal Article↗

PubMed2002

Optimum methamphetamine profiling with sample preparation by solid-phase microextraction.

Solid-phase microextraction (SPME) is a relatively new technique in which a small, polymer-coated fiber is employed to extract volatile and semivolatile organic compounds from the sealed headspace above a questioned sample. SPME, coupled with gas chromatography/mass spectrometry (GC/MS), was used to characterize impurities in illicit methamphetamine samples. Trace impurities present in a specimen were tentatively identified using mass-spectral databases and included 1,2-dimethyl-3-phenyl-aziridine (indicating synthesis via a halogenated ephedrine intermediate), ethyl vanillin (a flavoring compound), and caffeine (a stimulant used as cutting agent). The types and numbers of organic compounds sampled by SPME were compared with those collected by various solvent extraction protocols. In addition to unambiguously confirming the presence of methamphetamine, SPME-GC/MS analyses detected approximately 30 more organic analytes than were found by GC/MS following the ethyl acetate extraction method adopted by the United Nations International Drug Control Programme. SPME-GC/MS is a superior method for generating material "fingerprint" profiles in methamphetamine samples. The detection and characterization of increased points of comparison in drug samples provide more detailed chemical signatures for both intelligence and operational information.

Journal Article↗

PubMed2005

Structural determination of the principal byproduct of the lithium-ammonia reduction method of methamphetamine manufacture.

One common method of illicit methamphetamine manufacture utilizes an alkali metal, typically lithium, and liquid ammonia to chemically reduce ephedrine or pseudoephedrine to form methamphetamine. This method is often referred to as the lithium-ammonia reduction method or the Birch reduction method. While the hydroxyl group of ephedrine is more reactive than the aromatic ring, excess alkali metal and the presence of a proton source allow the formation of a cyclohexadiene byproduct not found in samples of methamphetamine produced from other manufacturing methods. A sample enriched in this byproduct was generated and characterized using nuclear magnetic resonance (NMR) spectroscopy, gas chromatography-mass spectrometry (GC-MS), infrared (IR) spectrophotometry, and ultraviolet (UV) spectrophotometry. The chemical structure of this byproduct was determined to be 1-(1',4'-cyclohexadienyl)-2-methylaminopropane (CMP).

Journal Article↗

PubMedDate not supplied

Psychiatric symptoms in methamphetamine users.

The Methamphetamine Treatment Project (MTP) offers the opportunity to examine co-occurring psychiatric conditions in a sample of 1016 methamphetamine users participating in a multisite outpatient treatment study between 1999-2001. Participants reported high levels of psychiatric symptoms, particularly depression and attempted suicide, but also anxiety and psychotic symptoms. They also reported high levels of problems controlling anger and violent behavior, with a correspondingly high frequency of assault and weapons charges. Findings continue to support the value of integrated treatment for co-occurring conditions, especially the importance of training counseling staff to handle psychotic symptoms when needed.

Adult↗

PubMed2004

A multi-site comparison of psychosocial approaches for the treatment of methamphetamine dependence.

AIMS: The Center for Substance Abuse Treatment (CSAT) Methamphetamine Treatment Project (MTP) is the largest randomized clinical trial of treatments for methamphetamine (MA) dependence to date. The objective of the study was to compare the Matrix Model, a manualized treatment method, with treatment-as-usual (TAU) in eight community out-patient settings in the Western United States. DESIGN: Over an 18-month period between 1999 and 2001, 978 treatment-seeking, MA-dependent people were randomly assigned to receive either TAU at each site or a manualized 16-week treatment (Matrix Model). SETTING: The study was conducted as an eight-site out-patient trial, with six sites located in California and one each in Montana and Hawaii. FINDINGS: In the overall sample, and in the majority of sites, those who were assigned to Matrix treatment attended more clinical sessions, stayed in treatment longer, provided more MA-free urine samples during the treatment period and had longer periods of MA abstinence than those assigned to receive TAU. Measures of drug use and functioning collected at treatment discharge and 6 months post-admission indicate significant improvement by participants in all sites and conditions when compared to baseline levels, but the superiority of the Matrix approach did not persist at these two timepoints. CONCLUSIONS: Study results demonstrate a significant initial step in documenting the efficacy of the Matrix approach. Although the superiority of the Matrix approach over TAU was not maintained at the post-treatment timepoints, the in-treatment benefit is an important demonstration of empirical support for this psychosocial treatment approach.

Adolescent↗

PubMedDate not supplied

Sonographic findings in methamphetamine-induced ischemic colitis.

Ischemic colitis is a clinicopathologic condition that commonly occurs in elderly patients with atherosclerotic disease or diabetes mellitus. Uncommon etiologies include vasculitis and use of drugs such as oral contraceptives, phenobarbital, nasal decongestants, dextroamphetamine, and cocaine. Recent studies have shown sonography and CT to be helpful in the evaluation of the colitides. We report the sonographic and CT findings in an unusual case of methamphetamine-induced ischemic colitis. Sonography and CT revealed diffuse thickening of the large bowel wall. Methamphetamine abuse should be considered in the differential diagnosis of the colitides, particularly in the setting of a young patient with a history of drug use and no other predisposing conditions.

Abdomen, Acute↗

PubMed1996

Contrasting effects of repeated treatment vs. withdrawal of methamphetamine on tyrosine hydroxylase messenger RNA levels in the ventral tegmental area and substantia nigra zona compacta of the rat brain.

We have assessed the effect of repeated treatment with methamphetamine (METH) on the abundance of the messenger ribonucleic acid molecules encoding the enzyme tyrosine hydroxylase (TH) and preprocholecystokinin (PPCCK) in the substantia nigra zona compacta (SNc) and the ventral tegmental area (VTA) by in situ hybridization histochemistry. Rats were injected twice daily with METH (4 mg/kg of body weight) for 6 consecutive days and sacrificed either 5 h or 15 days after the last injection. TH mRNA in the VTA was unaffected by repeated METH treatment but was decreased 25% relative to controls in the SNc. Concurrent administration of METH and MK-801 decreased TH mRNA levels in the SNc to 47% relative to controls. In contrast, TH mRNA levels were found increased in the VTA (42%) but not SNc 15 days post-METH treatment. Coadministration of MK-801 with METH prevented the increase in TH mRNA in the VTA. PPCCK mRNA levels were not significantly affected by METH treatment in VTA or SNc either 5 h or 15 days posttreatment. The results demonstrate that exposure to repeated methamphetamine elicits changes of TH mRNA levels in the VTA that become manifest 2 weeks after withdrawal from this psychostimulant drug.

Animals↗

PubMed2000

Long-term methamphetamine-induced decreases of [(11)C]WIN 35,428 binding in striatum are reduced by GDNF: PET studies in the vervet monkey.

The effects of glial cell line-derived neurotrophic factor (GDNF) pretreatment on methamphetamine (METH)-induced striatal dopamine system deficits in the vervet monkey were characterized with [(11)C]WIN 35,428 (WIN)-positron emission tomography (PET). WIN, a cocaine analog that binds to the dopamine transporter (DAT), was used to provide an index of striatal dopamine terminal integrity. In two subjects, GDNF (200 microg/40 microl) was injected into the caudate and putamen unilaterally vs. saline contralaterally. After 1-2 weeks, + and -GDNF striatal WIN-PET binding values were equivalent as calculated by multiple time graphic analysis, suggestive of an absence of unilateral DAT up-regulation. Three other subjects (n = 3) received GDNF injections into the caudate and putamen unilaterally and one week later, were administered METH HCl (2 x 2 mg/kg; i.m., 24 hours apart; a neurotoxic dosage for this species). At 1 week post-METH, WIN-PET studies showed that mean WIN binding was decreased by 72% in the +GDNF and by 92% in the -GDNF striatum relative to pre-drug assessment values. Thus, GDNF pretreatment reduced the extent of METH-induced decreases in WIN binding. Subsequent WIN-PET studies (1.5-9-month range) showed a protracted recovery of WIN binding in each striatum, indicative of long-term but partially reversible METH neurotoxicity. Further, at each time point, WIN binding remained relatively higher in the +GDNF vs. -GDNF striatum. These results provide further evidence that the adult non-human primate brain remains responsive to exogenously administered GDNF and that this pharmacotherapy approach can counteract aspects of neurotoxic actions associated with methamphetamine.

Animals↗

PubMed2001

Drugs of abuse in a non-conventional sample; detection of methamphetamine and its main metabolite, amphetamine in abusers' clothes by HPLC with UV and fluorescence detection.

In this paper, we report the detection of methamphetamine and its major metabolite, amphetamine, in garments belong to known-abusers. These compounds were extracted from the textile using a mixture of chloroform:propan-2-ol (3:1, v/v), derivatized with 4-(4,5-diphenyl-1H-imidazol-2-yl) benzoyl chloride and separated using a reversed-phase high-performance liquid chromatography. The derivatives were detected by measuring either fluorescence at 440 nm or absorbance at 330 nm. By using 1-methyl-3-phenyl propylamine as an internal standard, calibration curves of spiked textile samples were linear over a wide range with correlation coefficients of 0.997 or better. Detection limits at a signal-to-noise ratio of 3 were less than or equal to 37.3 and 0.4 pg on column for the high-performance liquid chromatography-ultraviolet and -fluorescence detection methods, respectively. Intra- and inter-day variations at high and low concentrations (n > or = 3) were < or =12.7%. The developed methods were successfully applied to the determination of methamphetamine and amphetamine in clothes samples belong to abusers.

1-Propanol↗

PubMed1986

Gas chromatographic/mass spectrometric determination of carbon isotope composition in unpurified samples: methamphetamine example.

A gas chromatograph/quadrupole mass spectrometer system, operated in electron impact/selected ion monitoring mode, is used to determine the intensity ratio of the m/z 59 and the m/z 58 ions of the [C3H8N]+ fragment derived from methamphetamine samples synthesized with varying amounts of 13C-labeled methylamine. Crude products are introduced into the gas chromatograph without prior cleanup. The ratios measured were in excellent agreement with those calculated. A change in 0.25% use of 13C-methylamine is sufficient for product differentiation. The feasibility of using isotope labeling and subsequent mass spectrometric isotope ratio measurement as the basis of a compound tracing mechanism is discussed. Specifically, if methamphetamine samples manufactured from legal sources are asked to incorporate distinct 13C compositions, their sources can be traced when samples are diverted into illegal channels. Samples derived from illicit preparations can also be traced if the manufacturers of a precursor (methylamine in this case) incorporate distinct 13C compositions in their products.

Carbon Isotopes↗

PubMed1975

Effects on offspring of chronic maternal methamphetamine exposure.

Twenty-five Sprague-Dawley derived rats were administered 1.0, 3.0 or 5.0 mg/kg of methamphetamine HC1 or saline twice daily throughout gestation beginning on Day 1 of pregnancy. Rats were allowed to deliver normally; offspring were culled to 8 and sexed on Day 7, and weaned on Day 21. All females had viable litters except at the 5.0 mg/kg dose where 4 of 7 failed to deliver. The rats given methamphetamine delivered earlier than did controls. Weight gain over gestation decreased as a function of increasing drug dose. No gross anomalies were visible in the offspring. Litter size decreased as a function of increased dose and eye opening was delayed in the drug groups; the 5.0 mg/kg offspring made more conditioned avoidance responses than did the 3.0 mg/kg and saline offspring.

Animals↗

PubMed1998

Effects of various anionic chiral selectors on the capillary electrophoresis separation of chiral phenethylamines and achiral neutral impurities present in illicit methamphetamine.

In this study, various anionic chiral selectors were investigated for the capillary electrophoresis (CE) separation of six chiral phenethylamines and three achiral neutral impurities which are commonly identified in illicit methamphetamine. Analyses were carried out at pH 8 (high osmotic flow) with untreated capillaries using 25 mM chiral surfactant or 10 mM charged cyclodextrin. The chiral selectors included the micelle (R)-N-dodecoxycarbonylvaline (EnantioSelect (R)-Val-1) (ES) and the cyclodextrins sulfobutyl(IV)-ether-beta-cyclodextrin (SBE(IV)-beta-CD) (BSB4), SBE(VII)-beta-CD (BSB7), SBE(XII)-beta-CD (BSB 12), SBE(IV)-gamma-CD (GSB-4), SBE(VII)-gamma-CD (GSB-7), sulfated(XI)-alpha-cyclodextrin (SU(XI)-alpha-CD (AS11), SU(VII)-beta-CD (BS7), SU(XII)-beta-CD (BS12) and SU(XIII)-beta-CD (GS13). Enantiomeric and achiral selectivity strongly depends on the size of the CD, the average degree of substitution, and the type of substitution. ES exhibits good performance for the neutral solutes, but exhibits enantiomeric selectivity only for the alpha-hydroxyphenethylamines. GS13 provides the best overall enantiomeric selectivity. All fifteen solutes related to methamphetamine are simultaneously separated using BSB7.

Anions↗

PubMed2002

Methamphetamine induces apoptosis in seminiferous tubules in male mice testis.

We investigated whether methamphetamine (MAMP) induces apoptosis in seminiferous tubules in 10-week-old male ICR mice. Methamphetamine was dissolved in saline and injected ip at four doses (1, 5, 10, and 15 mg/kg). TUNEL-positive cells were detected in the seminiferous tubules in animals 24 h after a single treatment with 5, 10, or 15 mg/kg MAMP. The percentage of seminiferous tubules containing more than three TUNEL-positive cells (apoptotic tubules) was considered a reliable indicator for apoptotic changes. After a single treatment with 10 mg/kg MAMP, the percentage of apoptotic tubules increased with time, and it became significant at 24 h, at which time vacuolar changes in spermatogonia also peaked. Although the percentage of apoptotic tubules increased dose dependently from 5 to 15 mg/kg MAMP, the DNA ladder was detected in the testis of 15 mg/kg MAMP-treated mice. Thus, we have demonstrated that MAMP induces apoptosis in seminiferous tubules in male mice testis.

Animals↗

PubMed1988

Simultaneous quantitative analysis of methamphetamine and 4-hydroxymethamphetamine in body fluids by gas chromatography/mass spectrometry.

Pentodeuterated 4-hydroxymethamphetamine (HMAMP-d5), 1-(4-hydroxyphenyl)-2-(methyl-d3-amino)-propane-1,2-d2 of high quality was prepared and proved to be a most useful internal standard for quantitative analyses of 4-hydroxymethamphetamine (HMAMP), a main metabolite of methamphetamine (MAMP). Highly reliable results were obtained by gas chromatography/mass spectrometry. Simultaneously we determined also MAMP, amphetamine (AMP), 4-hydroxyamphetamine (HAMP), and HMAMP in body fluids, using two internal standards, HMAMP-d5 for HMAMP and HAMP and pentodeuterated methamphetamine, 1-phenyl-2-(methyl-d3-amino)-propane-1,2-d2, for MAMP and AMP.

Amphetamine↗

PubMed1975

Modifications by lithium of behavioral responses to methamphetamine and tetrabenazine.

Different groups of mice were injected s.c. daily with lithium chloride in three doses(0.52, 1.58 and 4.72meg/kg) or with saline for a period of 3 weeks. Lithium administered acutely or chronically did not affect spontaneous locomotor activities. However, methamphetamine-induced hyper-locomotor activities were inhibited in the lithium groups as compared with those in the saline group, while the hyper-locomotor activities induced by tetrabenazine in the nialamide-pretreated animals were reduced to some extent but not significantly by lithium. Tetrabenazine brought about an initial transient increase followed by a decrease of spontaneous locomotor activities in the lithium groups, whereas it induced only a decrease of the activities in the saline group. In addition, jumping and vertical jumping behaviors, which were not observed in the saline group, occurred 30-60 min after tetrabenazine in the lithium groups. These effects of lithium tended to increase with an increase of the doses administered and with a prolongation of its daily administration. The results demonstrate that lithium modifies behavioral responses to methamphetamine and tetrabenazine.

Animals↗