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PubMed1987

Abuse of smoking methamphetamine mixed with tobacco: I. Inhalation efficiency and pyrolysis products of methamphetamine.

Experiments of smoking methamphetamine in tobacco have been investigated. Inhalation efficiencies of methamphetamine into tar were 6 to 17% according to the additive amounts, suction volume, and intervals of smoking. Major pyrolysis products of methamphetamine in tar were identified as methamphetamine, amphetamine, phenylacetone, dimethylamphetamine, N-formyl-, N-acetyl-, N-propionyl-, and N-cyanomethyl-methamphetamine by the spectral analysis of infrared spectra (IR), mass spectra (MS), and proton magnetic resonance spectra (PMR), and comparison with the samples synthesized from authentic samples by one step. The largest pyrolysis product was N-cyanomethylmethamphetamine which is a new compound and easily metabolized to methamphetamine in the body. Methamphetamine itself transferred into tar was not so large, but the total active compounds in tar which would be metabolized to methamphetamine in the body were considerably larger.

Administration, Inhalation↗

PubMed1982

Determination of d-methamphetamine in urine after administration of d- or dl-methamphetamine to rats by radioimmunoassay using optically sensitive antiserum.

A radioimmunoassay was developed for the determination of d-methamphetamine in urine. Antiserum to d-methamphetamine was prepared in rabbits by immunization with d-N-4-aminobutylmethamphetamine conjugated with bovine serum albumin. d-1-[3H]-Methamphetamine was used as a labeled compound for radioimmunoassay. The specificity of the antibody against d-methamphetamine was determined by cross-reaction studies with optical isomers of methamphetamine and its analogs. The antibody was specific for d-methamphetamine and exhibited no significant cross-reaction with the l-isomers. This stereoselective assay was applied to determination of d-methamphetamine excreted in urine after oral administration of d- or dl-methamphetamine to rats.

Animals↗

PubMed2006

A public health response to the methamphetamine epidemic: the implementation of contingency management to treat methamphetamine dependence.

BACKGROUND: In response to increases in methamphatemine-associated sexually transmitted diseases, the San Francisco Department of Public Health implemented a contingency management (CM) field program called the Positive Reinforcement Opportunity Project (PROP). METHODS: Methamphetamine-using men who have sex with men (MSM) in San Francisco qualified for PROP following expressed interest in the program, provision of an observed urine sample that tested positive for methamphetamine metabolites and self-report of recent methamphetamine use. For 12 weeks, PROP participants provided observed urine samples on Mondays, Wednesdays and Fridays and received vouchers of increasing value for each consecutive sample that tested negative to metabolites of methamphetamine. Vouchers were exchanged for goods and services that promoted a healthy lifestyle. No cash was provided. Primary outcomes included acceptability (number of enrollments/time), impact (clinical response to treatment and cost-effectiveness as cost per patient treated). RESULTS: Enrollment in PROP was brisk indicating its acceptability. During the first 10 months of operation, 143 men sought treatment and of these 77.6% were HIV-infected. Of those screened, 111 began CM treatment and averaged 15 (42%) methamphetamine-free urine samples out of a possible 36 samples during the 12-week treatment period; 60% completed 4 weeks of treatment; 48% 8 weeks and 30% 12 weeks. Across all participants, an average of $159 (SD = $165) in vouchers or 35.1% of the maximum possible ($453) was provided for these participants. The average cost per participant of the 143 treated was $800. CONCLUSION: Clinical responses to CM in PROP were similar to CM delivered in drug treatment programs, supporting the adaptability and effectiveness of CM to non-traditional drug treatment settings. Costs were reasonable and less than or comparable to other methamphetamine outpatient treatment programs. Further expansion of programs like PROP could address the increasing need for acceptable, feasible and cost-effective methamphetamine treatment in this group with exceptionally high rates of HIV-infection.

Adolescent↗

PubMedDate not supplied

Pharmacokinetics of methamphetamine self-administered to human subjects by smoking S-(+)-methamphetamine hydrochloride.

S-(+)-methamphetamine hydrochloride ("ice") is abused by smoking (inhaling the vapors of the material). Male human volunteers inhaled the drug from a pipe heated at 300 degrees-305 degrees C for an average inhaled dose of 21.8 +/- 0.3 (SE) mg. The same volunteers were given an intravenous injection of 15.5 mg of S-(+)-methamphetamine hydrochloride. Methamphetamine and its metabolite amphetamine were analyzed in plasma, saliva, and urine by gas chromatography. The bioavailability of smoked methamphetamine was 90.3 +/- 10.4%. (Oral bioavailability calculated from this study and a previous one was 67.2 +/- 3.1%). The geometric mean plasma half-life was 11.1 hr for smoked methamphetamine and 12.2 hr for the intravenous drug. These values agreed with urinary excretion rate data. The volume of distribution in the elimination phase was 3.24 +/- 0.36 liter/kg for the smoked dose and 3.73 +/- 0.59 liter/kg for the intravenous dose. The mean residence times were 11.5 +/- 0.5 hr and 11.3 +/- 1.74 hr for the two routes. Metabolic clearance represented 58 and 55%, respectively, of the total clearance. Significant amounts of the drug (37-45% of the nominal dose) were excreted in urine as methamphetamine and lesser amounts (7% of the nominal molar dose) as amphetamine. Renal clearance was equivalent for the two routes. Methamphetamine concentrations in plasma after inhalation showed a plateau. A model involving both a fast and a slow input function fit the data from 4 of the 6 subjects and indicated a terminal elimination rate that agreed with results from model-independent pharmacokinetic calculations. The drug caused significant subjective and cardiovascular effects.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Inhalation↗

PubMedDate not supplied

CI-mass fragmentographic analysis of methamphetamine and amphetamine in human autopsy tissues after acute methamphetamine poisoning.

A 22-year-old male methamphetamine abuser was put under police protection owing to his abnormal state of excitation, but died 1 h later. Distribution of methamphetamine and amphetamine in the body was analyzed by the chemical ionization mass fragmentographic method. Amphetamine/methamphetamine concentrations (mumol/100 g) were 0.24/5.59 in blood, 0.41/9.43 in liver, 0.41/10.02 in brain, 0.37/9.80 in kidney, 0.18/4.57 in muscle, 0.02/0.63 in subcutaneous fat and 1.87/1464 in gastric contents. Total amount of methamphetamine hydrochloride in stomach contents was about 54 mg. Amphetamine concentrations in tissues ranged from 3.2% to 4.3% of methamphetamine, and was 0.1% in stomach contents. Amphetamine in tissues seems to be a metabolite of methamphetamine, and amphetamine in gastric contents is presumed to result from gastric mucous excretion. The blood concentration of methamphetamine was at a fatal level, and the total amount of the drug in gastric contents indicates that fatal poisoning occurred by ingestion.

Adult↗

PubMed1998

Immunological analysis of methamphetamine antibody and its use for the detection of methamphetamine by capillary electrophoresis with laser-induced fluorescence.

An accurate, simple and rapid immunoassay is demonstrated for the detection of methamphetamine in urine by capillary electrophoresis (CE) with laser-induced fluorescence (LIF). An aminobutyl derivative of methamphetamine was conjugated with proteins, and used as an immunogen to produce antibodies for the assay. The methamphetamine derivative was also labeled with fluorescein isothiocyanate (FITC) to compete with free methamphetamine in the sample for the antibody binding site. Levels of free and antibody-bound FITC-labeled methamphetamine were monitored by performing CE-LIF using an untreated fused-silica column. This competitive immunoassay used antiserum instead of purified antibody or antibody fragment, yet was found to have good precision with a sensitivity of lower than 20 ng/ml. Various antibodies were also screened, and cross-reactivity of anti-MA antibody with methamphetamine analogues were also investigated. The results indicate that CE-LIF-based immunoassay is a powerful tool for the screening and characterization of antibody and may have possible applications in the detection of abused drugs in urine.

Animals↗

PubMed1995

Localization of the epitope in methamphetamine and its antibody use for the detection of methamphetamine and benzphetamine by polarization fluoroimmunoassay.

An antibody was prepared, using a four carbon-bridged methamphetamine molecule as an immunogen in order to develop a polarization fluoroimmunoassay for urine screening of methamphetamine and benzphetamine. Also, its binding characteristics were investigated to locate epitope sites of methamphetamine. The study showed that the antibody was highly capable of eliciting a polarization fluoroimmunoassay response. However, the detection limit was much greater for benzphetamine (0.05 ppm) than for methamphetamine (0.2 ppm) and weakly antibody binding was found with methamphetamine. This difference in sensitivity may reflect the similarity of benzphetamine to the immunogen used to produce the antibody. Both benzphetamine and the immunogen have a tertiary amine attached to a carbon bridges whereas methamphetamine has only a secondary amine and amphetamine has a primary amine group. The difference of cross-reactivity data between phenylethylamine drugs and beta-hydroxyl phenylethylamine drugs indicates that the beta-carbon position have a major influence on the antibody interaction. Thus, the substitution of hydroxyl group on beta-carbon resulted in virtually no antibody affinity, even if a tertiary amine or secondary amine group was present in the molecule. This suggests that the beta-carbon chain plays a primary role as the epitope site with cooperative binding site of tertiary amine or secondary amine in alpha-carbon position. A hydroxyl group at the beta-carbon position plays an important inhibitory role to the antibody binding.

Antibody Affinity↗

PubMedDate not supplied

Detection of D,L-amphetamine, D,L-methamphetamine, and illicit amphetamine analogs using diagnostic products corporation's amphetamine and methamphetamine radioimmunoassay.

Cross-reactivity with Diagnostic Products Corporation (DPC) amphetamine and methamphetamine radioimmunoassay (RIA) reagents was determined for amphetamine, methamphetamine, and a number of amphetamine analogs. Concentrations from 100 to 100,000 ng/mL were assayed. 3,4-Methylenedioxyamphetamine (MDA) and 3,4-methylenedioxymethamphetamine (MDMA) showed significant cross-reactivity for the amphetamine and methamphetamine reagents respectively. 4-Hydroxymethamphetamine, 3,4-methylenedioxyethylamphetamine (MDEA), and N,N-dimethyl-MDA also showed significant cross-reactivity with the methamphetamine reagents, but less than MDMA. None of the other analogs showed a positive result with the amphetamine or methamphetamine reagents at even the highest concentration, although several did show measurable cross-reactivity. The L isomers of amphetamine and methamphetamine showed substantially less cross-reactivity than the D forms to which the respective antibody systems are targeted.

3,4-Methylenedioxyamphetamine↗

PubMed1995

Comparative PET studies of the distribution of (-)-3,4-methylenedioxy-N-[11C]methamphetamine and (-)-[11C]methamphetamine in a monkey brain.

Carbon-11 labeled (-)-methamphetamine and (-)-3,4-methylenedioxy-N-methamphetamine were synthesized by methylation of the corresponding desmethyl precursors with [11C]H3I in 40-60% yield in a synthesis time of 30 min from EOB with a specific activity of 0.5-1.2 Ci/microM. PET studies in a Rhesus monkey revealed that the uptakes of both compounds in different brain regions were similar, and the retention of radioactivity in these brain regions remained constant throughout the study for the former while it was washed out slowly for the latter. The half-life of (-)-3,4-methylenedioxy-N-methamphetamine in monkey brain was approximately 70 min. Analyses of arterial plasma by HPLC revealed that 50% of radioactivity in the plasma remained as (-)-methamphetamine while only 3% remained as (-)-3,4-methylenedioxy-N-methamphetamine at 60 min post-injection. These results suggest that the uptakes of both compounds in monkey brain are probably not receptor mediated. Rather, blood flow, lipophilicity of the compounds or other transport mechanisms may play a role in their uptakes.

3,4-Methylenedioxyamphetamine↗

PubMed1984

Effects of repeated methamphetamine administration on methamphetamine self-administration in rhesus monkeys.

The effects of prolonged exposure to high doses of stimulants on stimulant self-administration in rhesus monkeys have not been established. In the present experiment, rates of methamphetamine self-administration as well as the effects of methamphetamine on food-maintained responding were determined before and after a regimen of repeated methamphetamine injections. Increases in self-administration of some doses of methamphetamine as well as tolerance to the rate-decreasing effects of the drug on food-maintained responding were observed following the repeated injection regimen. The results suggest that while tolerance may develop to the rate-decreasing effects of the drug, there may be an increased sensitivity to its reinforcing properties. In addition, since this injection regimen has been shown in previous studies to deplete central monoamines, especially dopamine, the results suggest a role for these monoamines in these behavioral effects of methamphetamine.

Animals↗

PubMed1993

Site dependence of methamphetamine concentrations in blood samples collected from cadavers of people who had been methamphetamine abusers.

Various blood samples were collected from heart cavities and blood vessels in eight autopsy cases of people who had been methamphetamine abusers. Methamphetamine and its metabolite, amphetamine, were determined by gas chromatography-mass spectrometry-selected ion monitoring. In four cases where left and right heart blood samples were collected, methamphetamine concentrations in the left heart blood samples were 1.9-2.6 times higher than those in the right heart blood samples. In three cases where pulmonary vein blood samples were collected, methamphetamine concentrations in the pulmonary vein blood samples were higher than those in other blood samples sites. To interpret the blood methamphetamine concentrations, site dependence should be taken into consideration.

Adult↗

PubMed1988

Urinary excretion of p-hydroxylated methamphetamine metabolites in man. II. Effect of alcohol intake on methamphetamine metabolism.

The effect of drinking alcoholic beverages on methamphetamine metabolism was investigated in man. The subjects, 97 males and 9 females, were divided into three groups by evaluation of their urinary pH; i.e., acidic, subacidic and neutral groups. The subjects in each group were further divided into ethanol-positive subjects and ethanol-negative subjects, depending on the presence or absence of ethanol in their urine. Gas chromatographic analysis showed the urinary concentrations of methamphetamine in the ethanol-positive subjects to be higher than those in the ethanol-negative subjects in both the acidic and subacidic urinary pH groups. Liquid chromatography, on the other hand, showed the urinary concentrations of p-hydroxymethamphetamine and p-hydroxyamphetamine for the ethanol-positive subjects to be lower than those for the ethanol-negative subjects in all three groups. The relative proportions of p-hydroxylated metabolites to unchanged methamphetamine in urine, therefore, were severely reduced in the ethanol-positive subjects. These results suggest that drinking alcoholic beverages probably results in a suppression of methamphetamine metabolism in man.

Adult↗

PubMed1995

alpha-Benzyl-N-methylphenethylamine (BNMPA), an impurity of illicit methamphetamine synthesis: pharmacological evaluation and interaction with methamphetamine.

Methamphetamine is a popular drug of abuse, readily synthesized in clandestine laboratories. Illicitly obtained methamphetamine is frequently impure, containing various purposefully added diluents and adulterants, as well as impurities of manufacture and origin. Few impurities have been studied in vivo and limited information exists concerning their pharmacology/toxicology. One such impurity of manufacture is alpha-benzyl-N-methylphenethylamine (BNMPA). Acute toxicity and spontaneous activity (locomotor) studies were conducted with this compound alone and in combination with S(+)-methamphetamine (METH) in male, ICR mice. In the acute toxicity studies, BNMPA was evaluated for convulsant activity. While BNMPA also produced some behavioral disturbances similar to those seen with methamphetamine (e.g., stereotopy) at doses greater than 30 mg/kg, no tonic-clonic convulsions were noted until pre-terminal convulsion at 50 mg/kg. METH alone produced tonic-clonic convulsions at terminal doses of 70 mg/kg. When BNMPA was given in combination with METH, there was no readily apparent change in the convulsion profile from that of METH given alone. In spontaneous activity studies, doses of BNMPA ranging from 1 mg/kg to 50mg/kg failed to alter locomotor activity significantly from controls though 5 mg/kg METH alone significantly increased spontaneous activity. In addition, increases in spontaneous activity elicited by 5 mg/kg METH were not affected when METH was given with 5 mg/kg BNMPA. While BNMPA appears to have toxic effects in the central nervous system (CNS), the failure to affect locomotor activity or alter either METH-induced increases in spontaneous activity or METH-induced convulsions suggests that the two agents are producing their effects through distinct mechanisms.

Animals↗

PubMed2005

Development of murine monoclonal antibodies to methamphetamine and methamphetamine analogues.

Methamphetamine and ecstasy are addictive drugs that cause major health problems in young people. Here we report on the development of high-affinity monoclonal antibodies to methamphetamine and its analogues, which may constitute powerful tools for antibody-based therapy. Six haptens, methamphetamine and ecstasy analogues, were synthesized, linked to a carrier protein and injected into mice. Several specific monoclonal antibodies were subsequently obtained following fusion of splenocytes from the immunized animals, with Sp2/O cells. Antibody specificity was fully investigated by competition ELISA, using a series of analogues, to identify specific amphetamine and/or ecstasy-specific antibodies. Antibody affinity was estimated to be in the range of 10(8) M(-1) with an enantiomeric hapten. Finally, two characteristic hybridoma clones (DAS-M243-6H5 and DAS-M278-4B12), secreting specific and potent mAbs were isolated. The development of drug-specific antibodies as in this study may provide promising therapeutic insight into how to neutralize methamphetamine in vivo during acute intoxication.

Animals↗

PubMed2001

Regional distribution of methamphetamine in autopsied brain of chronic human methamphetamine users.

We measured levels of methamphetamine and those of its metabolite amphetamine in 15 autopsied brain regions of 14 human methamphetamine users. Only slight regional differences were observed in drug concentrations among the brain areas. Although, some redistribution of the drugs probably occurred postmortem, these data suggest that methamphetamine might not be preferentially retained in dopamine-rich brain areas but is heterogenously distributed in brain of chronic human users of the drug. The possible pharmacological actions of methamphetamine in both dopamine-rich and poor brain areas of chronic drug users need to be considered.

Adult↗

PubMedDate not supplied

Conversion of methamphetamine to N-methyl-methamphetamine in formalin solutions.

Embalming is common, and yet it can create problems for the forensic scientist if a drug has been the cause of death and if this drug is also reactive toward the embalming fluid. Previous studies have focused on the amines such as nortriptyline, desipramine, and fenfluramine. In the presence of formalin, a typical component of embalming fluid, these compounds can be rapidly converted to their methylated derivatives amitriptyline, imipramine, and N-methyl-fenfluramine, respectively. We have begun a larger project designed to determine the reactivity and reactions of a wide range of drugs with formalin and have extended it to amphetamines. We report here our results from methamphetamine, which is converted into its N-methyl derivative in the presence of formalin. The rate of conversion is dependent upon pH and formalin concentration with the greatest conversion occurring under basic conditions and the highest formalin concentration. Up to 100% conversion in 24 h was observed under certain conditions. When studied in human tissue exposed to methamphetamine and treated with formalin, again, conversion to N-methyl-methamphetamine was readily apparent as early as 30 min after exposure to formalin. Finally, we note that the reactions of methamphetamine with formalin studied here are probably general and should be considered when performing postmortem/postembalming forensic analysis.

Central Nervous System Stimulants↗

PubMedDate not supplied

alpha-benzyl-N-methylphenethylamine (BNMPA), an impurity of illicit methamphetamine synthesis: III. Detection of BNMPA and metabolites in urine of methamphetamine users.

Eighty urine specimens collected from drug rehabilitation programs, which had been screened by immunoassay and confirmed positive by gas chromatography-mass spectrometry (GC-MS) for methamphetamine, were further analyzed for alpha-benzyl-N-methylphenethylamine (BNMPA) and its urinary metabolites, N-demethyl-BNMPA, diphenyl-2-propanone (DP2P), diphenyl-2-propanol, p-OH-N-demethyl-BNMPA, and p-OH-BNMPA. BNMPA is an impurity of illicit methamphetamine synthesis. Analysis of BNMPA and its metabolites was performed by quantitative GC-MS following beta-glucuronidase hydrolysis, liquid-liquid extraction, and derivatization with heptafluorobutyric anhydride. Two urine specimens contained detectable amounts of BNMPA and/or its metabolites. One contained trace amounts (greater than the limit of detection but less than the limit of quantitation) of N-demethyl-BNMPA and DP2P, as well as 0.04 mg/L p-OH-N-demethyl-BNMPA. The other contained trace amounts of BNMPA, p-OH-BNMPA, and p-OH-N-demethyl-BNMPA, as well as 0.03 mg/L N-demethyl-BNMPA. Prior to analyzing these urine specimens, pure reference material of p-OH-BNMPA was made available, and analysis confirmed our previous tentative identification of p-OH-BNMPA as a major metabolite of BNMPA. Detection of BNMPA or its metabolites in biological samples may serve as a marker of illicit methamphetamine administration.

Amphetamine↗

PubMed1994

A visual membrane immunoassay for the detection of methamphetamine using an enzyme-labeled tracer derived from methamphetamine and amphetamine.

A visual membrane enzyme immunoassay is described for the measurement of methamphetamine in urine. To increase assay sensitivity, tracers with chemically similar structures were cross-checked with the antibodies to determine their influence on the antibody binding. Tracers of horseradish peroxidase-labeled methamphetamine (MA-HRP) and amphetamine (A-HRP) derivatives were prepared for this purpose. Significant differences in antibody specificity were found between the two tracers. Based on the results of this study, a pair of an antibody and a tracer was selected and a membrane enzyme immunoassay (EIA) was developed utilizing the competitive binding between methamphetamine and the drug-HRP tracer. UltraBind membrane (0.45 micron) was used as the solid matrix to which the antibody was attached. Using diaminobenzidine substrate with Co2+ ion, a stable grey color appeared on the surface of membrane for MA-negative urine samples. No color appeared for MA-positive urine with a cut-off level of 0.8 ppm.

Amphetamines↗