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PubMed1986

Methaqualone withdrawal syndrome with photoparoxysmal responses and high-amplitude visual evoked potentials.

Methaqualone is a sedative hypnotic that is often abused. Tolerance and habituation may develop, and the withdrawal syndrome may include seizures. In the patient studied, methaqualone withdrawal was manifested by myoclonic and tonic-clonic seizures, an EEG photoparoxysmal response (PPR), and a high-amplitude visual evoked potential (VEP) to pattern-reversal stimuli. The EEG and VEP returned to normal after resolution of the withdrawal state. Substance withdrawal should be considered in the differential diagnosis of PPR or of an unusually high-amplitude VEP in a person with no previous history of epilepsy. Disappearance of these phenomena may be a useful indicator of the end of the withdrawal state.

Adult↗
PubMed1976

Urinary excretion of c-hydroxy derivatives of methaqualone in man.

1. Six monohydroxy metabolites of methaqualone have been identified by g.l.c.-mass spectrometry in the urine of healthy human subjects who received therapeutic doses (250 mg) of the drug (Melsed) daily for ten day. 2. The three major metabolites were 2-methyl-3-(2'-hydroxymethylphenyl)-4(3H)-quinazolinone, 2-methyl-3-(2'-methyl-3'-hydroxyphenyl)-4(3H)-quinazolinone and 2-methyl-3-(2'-methyl-4'-hydroxyphenyl)-4(3H)-quinazolinone. Three minor metabolites in descending order of importance were 2-hydroxymethyl-3-o-tolyl-4(3H)-quinazolinone, 2-methyl-6-hydroxy-3-o-tolyl-4(3H)-quinazolinone and 2-methyl-8-hydroxy-3-o-tolyl-4(3H)-quinazolinone. 3. The 8-hydroxy metabolite is identified as a urinary metabolite or methaqualone in humans for the first time.

Administration, Oral↗
PubMed1976

Methaqualone (Mandrax) abuse, urine testing, and identification: clinical correlation between a new mass urinalysis test and a military drug abuse program.

A urine test presently based on thin-layer chromatography screening and gas-liquid chromatography (GLC) confirmation has been a practical way of detecting methaqualone use in individuals. A more practical test is the radioimmuno assay for screening and GLC for confirmation. It appears that the drug methaqualone can be easily detected in the urine up to 72 hr after the last dosage. Individuals evaluated after being identified through the urine testing procedure readily admit to the use of illegal drugs and are most cooperative in giving drug abuse data, whether it is Mandrax, hashish, herion, or alcohol. The majority evaluated in this study were not in any program for drug abuse although all but one admitted to frequent drug abuse. The finding has been generally true of the other urinalysis test for drugs of abuse as the majority of the soldiers in the rehabilitation program have been identified by urinalysis over the past year. Because of the uncertainty of surveys on how prevalent was Mandrax use (anywhere from 5 to 90%, depending on who was consulted), a random selection of urines was done in September/November 1973. A total of 7,545 urine samples were tested those 2 months and the results were 2.9 and 3.9% positive respectively. Since that time and through June 1974 approximately 250 urine samples a week were tested for Mandrax based on a special request by the commander who suspected an individual of abusing Mandrax, and approximately 20 to 30% of the samples were positive. During June and July all randomly collected urines were tested and the results on a daily basis were from 1.5 to 3.5%. Since July 1974 no urines have been collected or tested. The follow-up indicates that of this number practically all are clinically confirmed as drug abusers and are entered into the Army's Drug Rehabilitation Program.

Adolescent↗
PubMed1978

Methaqualone abuse among U.S. army troops stationed in Europe.

Methaqualone (primarily Mandrax) abuse among United States troops stationed in Europe increased significantly from 1972 onward as seen by morbidity reports related to medical treatment and mortality studies related to autopsy toxicology reports. Rarely was methaqualone used alone. It was generally combined with alcohol and hashish, the combination of which resulted in an extremely dangerous situation for both the individual and society.

Alcohol Drinking↗
PubMed1988

Comparative study of the abuse liability of alprazolam, lorazepam, diazepam, methaqualone, and placebo.

Subjective effects of two benzodiazepines--alprazolam and lorazepam--were compared with two drugs of known abuse potential--diazepam and methaqualone--and placebo. This double-blind, crossover trial tested 30 casual recreational sedative users in a seminaturalistic setting. Methaqualone was more euphoriant and less sedative than the benzodiazepines. Diazepam and lorazepam were more euphoriant than placebo; alprazolam's euphoriant effect did not differ from these treatments. On other measures of abuse liability the benzodiazepines rated similarly, diazepam rating highest.

Adolescent↗
PubMed1980

Methaqualone RIA structure versus reactivity.

Fourteen different methaqualone-related substances (substituted 2-methyl-3-phenyl-4-quinazolinones) were analyzed by radioimmunoassay (RIA) at several different concentrations. An attempt is made to relate structural differences to the affinity of the compounds for the Roche RIA methaqualone antibody. The effects of substituent placement on the 2-methyl-3-phenyl-4-quinazolinone molecule are studied. Addition of a group to the para-position of the 3-phenyl group increased affinity, but alteration of other key functional groups had a reverse effect.

Methaqualone↗
PubMed1978

[Regional variations and particle binding of free amino acids in the rat brain: effects of amphetamine and methaqualone].

Amphetamine and methaqualone affected aspartate level in various regions of Rat brain. Increased aspartate level in cerebral cortex of methaqualone treated Rats was produced in the aspartate fraction whose binding to subcellular particules was Na+ dependant. This work suggest that aspartate level was altered only in brain fraction implicated in the pharmacological effects of the drugs.

Alanine↗
PubMed1977

Effects of serotonergic drugs on methaqualone-induced hypothermia.

Methaqualone (75 mg/kg) produced a significant decrease in the rectal temperature of mice. This effect was antagonized by parachlorophenylalanine and potentiated by Lilly 110140. These compounds also decreased and increased respectively the circulating concentration of methaqualone.

Animals↗
PubMedDate not supplied

Simultaneous determination of dextropropoxyphene, norpropoxyphene and methaqualone in plasma by gas chromatography with selective nitrogen detection.

A method for the identification and quantification of dextropropoxyphene, norpropoxyphene, and methaqualone in plasma by GC/NPD is presented. The procedure employs cyclizine as the internal standard and requires no derivatization. After a single-step extraction, analysis is achieved in 8 min. The lower limits of detection were found to be 6, 12, and 1 ng/ml for dextropropoxyphene, norpropoxyphene, and methaqualone, respectively. This method appears to be rapid, sensitive, and applicable to forensic and clinical toxicological analyses.

Chromatography, Gas↗
PubMed1985

[Photochemical reactivity of methaqualone-1-oxide].

The photoreactivity of methaqualone-1-oxide a main metabolite of the hypnotic methaqualone has been studied in polar and apolar solvents using UV- and daylight. Five photoproducts were isolated and identified by their analytical behaviour (TLC, UV, IR, high-resolution MS). The structure of the compounds 4, 6, 7, and 8 refer to unstable, reactive intermediates (oxaziridine, biradical) during the photolysis.

Chromatography, Thin Layer↗
PubMed1977

Collaborative study of gas-liquid chromatographic determination of methaqualone in pharmaceutical and clandestine preparations.

Eight laboratories collaboratively studied a procedure for the quantitative determination of methaqualone. HC1 in pharmaceutical and clandestine preparations. Methaqualone is extracted from an aqueous bicarbonate solution into chloroform and quantitated by gas-liquid chromatography on a 3% OV-1 column. Tetraphenylethylene is used as an internal standard. Two commerical preparations and 4 sample mixtures prepared by the author were studied. Recoveries for the 4 prepared samples ranged from 100.0 to 102.6%, and the coefficients of variation ranged from 1.58 to 4.15% for the 6 samples studied. The method has been adopted as official first action.

Chromatography, Gas↗
PubMed1978

Interaction of ethanol with amylobarbitone, phenobarbitone and methaqualone.

The presence and mechanism of synergism of action between ethanol and amylobarbitone, phenobarbitone or methaqualone was determined by application of simple pharmacokinetic models to log dose-response curves and plasma concentration-time curves for the hypnotics alone or when ethanol was given concurrently. For all three hypnotics, ethanol was found to increase the duration of hypnosis, but the mechanism of action was different for each. A sub-hypnotic dose of ethanol increased the volume of distribution of amylobarbitone and the consequent reduction in fractional elimination prolonged the half-life of the hypnotic. The distribution and elimination of methaqualone were not affected by ethanol, but there was a sensitisation of the target organ, shown by a reduced minimum effective dose. The minimum effective dose of phenobarbitone was also reduced by ethanol, but in addition, the rate of elimination of phenobarbitone was increased after the period of hypnosis.

Amobarbital↗
PubMed1982

Induction of hepatic UDP-glucuronyltransferase by oral methaqualone consumption.

Repeated oral administration of methaqualone (100 mg/kg/day) to rats for 6 consecutive days evoked approximately two and a half fold increase in p-nitrophenol glucuronidation by hepatic microsomes. Interestingly, the magnitude of UDP-glucuronyltransferase stimulation by methaqualone, when assessed in crude liver homogenate, was comparable to that obtained with isolated microsomes.

Administration, Oral↗
PubMed2001

Enantiomeric analysis of the five major monohydroxylated metabolites of methaqualone in human urine by chiral capillary electrophoresis.

Methaqualone (MQ; 2-methyl-3-o-tolylquinazolin-4(3H)-one) is a hypnotic and anticonvulsive drug in which the rotation about the nitrogen-to-aryl bond between the planar 2-methyl-quinazolin-4(3H)-one structure and the o-tolyl moiety is sterically hindered at body temperature. MQ and its five major monohydroxylated metabolites found in urine, 4'-hydroxymethaqualone (4'OH-MQ), 2'-hydroxymethaqualone (2'-OH-MQ), 3'-hydroxymethaqualone (3'OH-MQ), 2-hydroxymethaqualone (2OH-MQ) and 6-hydroxymethaqualone (6OH-MQ), are thus chiral substances whose enantiomers are shown to be separable by chiral capillary electrophoresis at pH 2.1 in the presence of 50 mM (2-hydroxypropyl)-beta-cyclodextrin (OHP-beta-CD). Other neutral derivatives of beta-CD, namely (2-hydroxypropyl)-gamma-CD, (2,3,6-trimethyl)-beta-CD, and (2,6-di-O-methyl)-beta-CD were found to be able to resolve the enantiomers of some but not all of these six components. With OHP-beta-CD, simultaneous analysis of the enantiomers of MQ and its five metabolites is hampered by the difficulty in separating MQ and 4'OH-MQ, the major urinary metabolite. A two-step solid phase extraction process is shown to permit discrimination between these two compounds and thus analysis of MQ enantiomers in unhydrolyzed urines that were collected overnight after administration of 250 mg of racemic MQ. Furthermore, analysis of liquid/liquid or solid-phase extracts of enzymatically hydrolyzed urines reveals the distribution of the enantiomers of the five hydroxymetabolites of MQ and, for the first time, insight into the stereoselectivity of the MQ metabolism. The major metabolite, 4'OH-MQ, is shown to be excreted almost exclusively as single enantiomer. The two urinary enantiomers of 6OH-MQ are present at about equal amounts, whereas unequal amounts are noted for the enantiomers of 3'OH-MQ, 2OH-MQ, and 2'OH-MQ.

Cyclodextrins↗
PubMed2003

Assessment of the stereoselective metabolism of methaqualone in man by capillary electrophoresis.

Methaqualone (MQ) and its hydroxylated metabolites are quinazoline derivatives that exhibit atropisomerism. As a continuation of our previous work with these compounds (Electrophoresis 2001, 22, 3270-3280), chiral capillary zone electrophoresis with hydroxypropyl-beta-cyclodextrin as buffer additive and multiwavelength absorbance detection is shown to be an effective tool to provide insight into the stereoselectivity of the MQ metabolism. The five major monohydroxy MQ metabolites formed during biotransformation do not show enantiomerization at temperatures up to 85 degrees C. Enzymatic and acidic hydrolysis of urines that were collected after concomitant administration of 250 mg of MQ and 25 mg diphenhydramine (DH) chloride are both shown to provide stereoselective metabolic patterns with 4'-hydroxymethaqualone, the major urinary metabolite, being excreted almost exclusively as a single enantiomer. A stereoselectivity in the formation of 2'-hydroxymethaqualone and 2-hydroxymethaqualone was also observed in vitro using human liver microsomes and preparations containing the cytochrome P450 enzyme (CYP) CYP3A4 only. The presence of DH during incubation with human liver microsomes did not reveal a difference in the metabolic pattern obtained. Furthermore, CYP2D6 and CYP2C19 do not significantly contribute to the metabolism of MQ. This was independently observed in vitro and via analysis of urines of individuals that are either efficient metabolizer phenotypes or poor metabolizer phenotypes for the two polymorphic enzymes. Although interindividual differences in the monitored metabolic patterns were noted, no marked difference could be related to a CYP2D6 or CYP2C19 polymorphism.

Biotransformation↗
PubMed1978

Synthesis of methaqualone and its diphasic titration in pure and tablet forms.

A one-step synthesis of methaqualone from N-acetylanthranilic acid and o-toluidine in the absence of a catalyst is described. A rapid diphasic titration procedure for its microestimation in pure and tablet forms, using dioctyl sodium sulfosuccinate and dimethyl yellow screened with oracet blue B, is proposed. The data were compared with those obtained from nonaqueous titration methods.

Methaqualone↗
PubMed1982

Metabolic oxidation of methaqualone in extensive and poor metabolisers of debrisoquine.

The metabolism of methaqualone to the glucuronides of 5 C-monohydroxy metabolites and to the N-oxide has been studied in 2 groups of healthy young adults phenotyped as extensive and poor metabolisers of debrisoquine. No significant interphenotype differences were observed with respect to the excretion of any of the 6 metabolites. It is probable that the genetic regulation of the pathways leading to these metabolites is at a locus other than that which is responsible for the regulation of the oxidation of debrisoquine, guanoxan, phenacetin, phenytoin and sparteine.

Adult↗