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Female mice which received chlordiazepoxide, diazepam, oxazepam, prazepam, flurazepam, or nitrazepam prenatally and postnatally had delays in the age of vaginal perforation and first estrus concomitant with reduced postnatal growth. Females exposed prenatally showed no growth deficits, but in four treatments had delayed vaginal opening. However, the age of first estrus was generally less than the control.
The article describes analytical data (TLC, IR, MS) of 7-chloro-1-methyl-1,3-hydroxy-5-phenyl-2H-1,4-benzodiazepin-2-one (3-hydroxydiazepam) and 7-cyclopropyl-methyl-1,3-dihydro-3-hydroxy-5-phenyl-2H-1,4-benzodiazpin-2-one (3-hydroxy-prazepam). Analytical properties of important derivatives (N-oxides, 3-acetoxy compounds, re-arrangement products) are also reported. Besides preparation methods are given for the synthesis of these substances, considering in particular preparation as solution-reactions as well as reaction on the TLC-plate.
A liquid chromatographic/mass spectrometric assay with atmospheric pressure chemical ionization (LC/APCI-MS) is presented for fast and reliable screening and identification and also for precise and sensitive quantification in plasma of the 23 benzodiazepines alprazolam, bromazepam, brotizolam, camazepam, chlordiazepoxide, clobazam, clonazepam, diazepam, flunitrazepam, flurazepam, desalkylflurazepam, lorazepam, lormetazepam, medazepam, metaclazepam, midazolam, nitrazepam, nordazepam, oxazepam, prazepam, temazepam and tetrazepam, triazolam, their antagonist flumazenil and the benzodiazepine BZ1 (omega 1) receptor agonists zaleplone, zolpidem and zopiclone. It allows confirmation of the diagnosis of an overdose situation and monitoring of psychiatric patients' compliance. The analytes were isolated from plasma using liquid-liquid extraction and were separated on a Merck LiChroCART column with Superspher 60 RP Select B as the stationary phase. Gradient elution was performed using aqueous ammonium formate and acetonitrile. After screening and identification in the scan mode using the authors' LC/MS library, the analytes were quantified in the selected-ion monitoring mode. The quantification assay was fully validated. It was found to be selective proved to be linear from sub-therapeutic to over therapeutic concentrations for all analytes, except bromazepam. The corresponding reference levels the assay's accuracy and precision data for all studied substances are listed. The accuracy and precision data were within the required limits with the exception of those for bromazepam. The analytes were stable in frozen plasma for at least 1 month. The validated assay was successfully applied to several authentic plasma samples from patients treated or intoxicated with various benzodiazepines or with zaleplone, zolpidem or zopiclone. It has proven to be appropriate for the isolation, separation, screening, identification and quantification of the drugs mentioned above in plasma for clinical toxicology, e.g. in cases of poisoning, and forensic toxicology, e.g. in cases of driving under the influence of drugs.
A method to prepare isolated hepatocytes from the small amounts of liver or liver fragments obtained from the human fetus following therapeutic abortion in early pregnancy is described. The hepatocytes have been characterized by electron microscopy and by their ability to dealkylate the benzodiazepine drug prazepam. The preparation of hepatocytes from a liver sample obtained from a kidney transplant donor is described and discussed.
The metabolism of diazepam has been studied in vitro using microsomal preparations from five human livers. An HPLC method was developed for the assay of diazepam, its congeners and its metabolites. Various methods for the incorporation of diazepam into the incubation medium were explored. It was shown that the use of organic solvents or small quantities of hydrochloric acid enhanced the solubility of this substrate. However all of the organic solvents tested were associated with substantial (around 50%) inhibition of metabolism of diazepam by both major pathways (N-demethylation and C3-hydroxylation). The use of hydrochloric acid gave satisfactory solubilization of diazepam, but not of pinazepam, prazepam or halazepam. Detailed metabolic studies were conducted only for diazepam, using neither hydrochloric acid nor organic solvents in the incubation medium. Formation of N-desmethyl-diazepam increased approximately linearly with diazepam concentration to 200 microM, and did not show saturation. Formation of temazepam gave a curved profile over the same range of diazepam concentrations, suggestive of a sigmoidal relationship. Michaelis-Menten parameters could not be determined for either reaction, but intrinsic clearances for N-demethylation varied over a 6-fold range. Diazepam N-demethylation was apparently promoted by the inclusion of temazepam in the incubation medium, while C3-hydroxylation of diazepam was enhanced in the presence of N-desmethyldiazepam. Mephenytoin in the incubation mixture had no effect on diazepam metabolism by either pathway. The present studies have defined some of the methodological problems inherent in in vitro metabolic studies with benzodiazepines, and have shed further light on the metabolism of diazepam in vitro by human liver.
1. The behavioural and anticonvulsant effects of 10 1,4-benzodiazepine derivatives were studied after intraperitoneal administration in DBA/2 mice, a strain genetically susceptible to sound-induced seizures. 2. The anticonvulsant effects were evaluated on seizures evoked by means of auditory stimulation (109 dB, 12-16 kHz) in animals placed singly under a perspex dome. The rank order of potency for anticonvulsant activity was alprazolam > clonazepam > flunitrazepam > diazepam > pinazepam > desmethyldiazepam > oxazepam > prazepam > halazepam > camazepam. 3. The impairment of locomotor performance following IP administration of the above reported derivatives was also evaluated by means of the rotarod test. 4. Hypothermic activity was observed after the highest doses of the benzodiazepines studied. 5. The potency of various 1,4-benzodiazepines as inhibitors of specific [3H] flumazenil binding to membranes from cerebellum or cortex was evaluated. In general, 1,4-benzodiazepines were active as anticonvulsants at micromolar range and inhibited [3H] flumazenil binding at nanomolar range. 6. The different degree of anticonvulsant activity and impairment of coordinated motor movements cannot be directly related to the benzodiazepine binding affinity or to the lipophilicity of the compounds studied.
A method for the identification and differentiation of the following benzodiazepines and their metabolites in urine after acid hydrolysis and acetylation is described: bromazepam, camazepam, chlordiazepoxide, clobazam, clonazepam, clorazepate, clotiazepam, cloxazolam, delorazepam, diazepam, ethylloflazepate, flunitrazepam, flurazepam, halazepam, ketazolam, loprazolam, lorazepam, lormetazepam, medazepam, metaclazepam, midazolam, nitrazepam, nordazepam, oxazepam, oxazolam, prazepam, quazepam, temazepam and tetrazepam. The acetylated extract was analysed by computerized gas chromatography-mass spectrometry. An on-line computer allowed rapid detection using ion chromatography with ions m/z 205, 211, 230, 241, 245, 249, 312 and 333. The identity of positive signals in the reconstructed ion chromatogram was confirmed by a comparison of the stored full mass spectra with reference spectra. The ion chromatograms, reference mass spectra and gas chromatographic retention indices (on OV-101) are documented.
A sensitive and specific determination of benzodiazepines in biological fluids is described, based on reversed-phase high-performance liquid chromatography. The compounds are extracted with a C2 AASP cartridge within 5 min. The recovery ranges from 92 to 104% and is independent of the concentration. Using a suitable gradient elution, complete separation of nineteen benzodiazepines is achieved in 50 min with detection limits of less than 3 ng/ml in urine and 5 ng/ml in other biological fluids. Using a rapid-scanning multichannel detector, the identities of the benzodiazepines can be confirmed. Prazepam is employed as internal standard. The precision and accuracy of the described method are suitable for monitoring benzodiazepine levels in clinical studies and an example is given.
A gas chromatographic technique for determining zopiclone based on a solid-phase extraction procedure with C18 cartridge for sample clean-up is presented. Quantification can be achieved with 1 ml of plasma. The method uses prazepam as internal standard. Zopiclone is separated on a 5% phenyl methyl silicone analytical column and detected with an electron-capture detector, which consequently allows a limit of quantitation of 2 micrograms/l. It is thus simple, rapid, sensitive and linear over the range 5-2000 micrograms/l.
A rapid twin-column gas chromatographic (GC) method for simultaneous screening and determination of commonly prescribed benzodiazepines and other new anxiolytics from plasma is described. Identical fused-silica Ultra 2 (5% phenyl methyl silicone) columns were connected to nitrogen-phosphorus and electron-capture detectors. The drugs were isolated from 1 ml of plasma by solid-phase extraction (SPE) onto a C8 reversed-phase sorbent and recovered with 0.5% acetic acid in methanol. The eluate was reconstituted with isopropanol which was found suitable for on-column injection. Prazepam was used as internal standard. The method was found appropriate for the quantification in a single run of alpidem, alprazolam, buspirone, chlordiazepoxide, clobazam, clotiazepam, diazepam, estazolam, flunitrazepam, lorazepam, midazolam, oxazepam, tofisopam, triazolam, and zolpidem within 30 min. Limits of quantification allow toxicological or pharmacological determinations, except for buspirone: only toxic blood levels can be quantified by this method. This first SPE of imidazopyridines (alpidem and zolpidem) provides faster, more efficient and cheaper sample preparation than the traditional liquid-liquid procedure. This GC analysis of alpidem and zolpidem is also the first described procedure for simultaneous quantification of all different classes of anxiolytics.
A simple high-performance liquid chromatographic method for the measurement of diazepam (DZP) and its major metabolites, N-desmethyldiazepam (DMDZP), temazepam (TZP) and oxazepam (OZP) in urine was developed. Preliminary studies of DZP metabolism were also undertaken in four healthy volunteers after administration of a single oral dose (4 mg) of DZP. The assay allowed the simultaneous determination of all analytes in 1 ml of urine and the detection limit was 2 ng/ml with a signal-to-noise ratio of 3. None of 22 drugs and 17 metabolites, except for mianserin, maprotiline and imipramine N-oxide, interfered with the detection of DZP metabolites. Recoveries of the analytes and the internal standard (prazepam) were > 82%. Intra- and inter-assay coefficients of variation for all analytes were < 5.5 and 4.1%, respectively. The mean (+/- S.D.) cumulative urinary excretions of DMDZP, TZP and OZP over 96 h after a single oral administration of DZP were 3.9 +/- 0.4, 6.6 +/- 1.4 and 2.8 +/- 0.6% of the dose, respectively. The urinary excretion of DZP was under the detection limit.
The solid-phase extraction (SPE) of seven 1,4-benzodiazepines (oxazepam, diazepam, temazepam, nordazepam, brotizolam, adinazolam and midazolam) using prazepam as internal standard was investigated. The 1,4-benzodiazepines were recovered from an aqueous buffer of suitable pH, using C18 Sep-Pak cartridges and mixtures of methanol-water as elution solvent. The recovery of oxazepam using different sorbent materials (C2, C8, C18, cyanopropyl, phenyl and cyclohexyl Bond-Elut) was also examined as a function of pH and the composition of the elution solvent. The SPE of oxazepam was investigated using spiked urine samples and the C2 cartridge gave rise to the cleanest urine extracts. The recoveries of the other 1,4-benzodiazepines from spiked urine and plasma samples using the C2 cartridge was then found to be higher than 90%, without any interference from endogenous compounds of the samples. Finally, the influence of other factors such as drug concentration, sample volume and the number of times the SPE cartridge had been used was also examined.
Colchicine overdose is uncommon but potentially life threatening because of the high toxicity of the drug. Poisoning by colchicine may occur following ingestion of medication used in acute attacks of gout and inflammatory diseases. We describe two cases involving suicide by the ingestion of medications marketed in France. In case 1, only heart blood was taken after body external examination. In case 2 an autopsy was performed and heart blood, urine, gastric contents and bile were taken for toxicological analysis. Colchicine was assayed in biological specimens by an HPLC-DAD method, after extraction by dichloromethane at pH 8, adding prazepam as internal standard (IS). Analyses were performed on a Symetry C-8 column. Mobile phase was a gradient of acetonitrile/pH 3.8 phosphate buffer. Colchicine is eluted at 13.1 min and the method is linear for blood, urine and bile over the range 4-1000 ng/mL. LOQ is 4 ng/mL. The concentrations of colchicine detected are: case 1: heart blood 13 ng/mL; case 2: heart blood 66 ng/mL, urine 500 ng/mL, gastric content 12 ng/mL, bile 5632 ng/mL. Our findings are in the range of lethal concentrations previously described, but there is no correlation with the amount of ingested drug. Even after massive overdose, it could be impossible to detect colchicine in blood, and as there is a widespread enterohepatic recirculation before excretion in bile and feces, bile is the target sample to analyse. We conclude in both cases that the cause of death was suicide with colchicine. It appears very important to perform an autopsy in order to obtain bile, urine, heart blood and femoral blood.
Clobazam (Castillium, Urbanil), a benzodiazepine often used as an anxiolytic and in the treatment of epilepsy, is considered a relatively safe drug. The authors present a fatal case with a 49-year-old female, found dead at home. She had been undergoing psychiatric treatment and was a chronic alcoholic. The autopsy findings were unremarkable, except for multivisceral congestion, steatosis and a small piece of a plastic blister pack in the stomach. Bronchopneumonia, bronchitis and bronchiolitis were also diagnosed. Anhigh-performance liquid chromatography (HPLC)/diode array detector (DAD)/mass spectrometry detection (MSD) with electrospray method was developed in order to detect, confirm and quantify clobazam in the post-mortem samples. In the chromatographic separation, a reversed-phase column C18 (2.1 x 150 mm, 3.5 microm) was used with a mobile phase of methanol and water, at a 0.25 ml/min flow rate. Carbonate buffer (pH 10.5) and 20 microl of prazepam (100 microg/ml) as internal standard were added to the samples. A simple and reliable liquid-liquid extraction method for the determination of clobazam in post-mortem samples was described. Calibration curves for clobazam were performed in blood, achieving linearity between 0.01 and 10 microg/ml and a detection limit of 1.0 ng/ml. The clobazam concentration found in post-mortem blood was 3.9 microg/ml, higher than the reported therapeutic concentration (0.1-0.4 microg/ml). The simultaneous acquisition by photodiode array detection and mass spectrometry detection results allowed benzodiazepines to be identified with sufficient certainty. An examination of all the available information suggested that death resulted from respiratory depression due to clobazam toxicity.
Drug screening methods were developed to detect alprazolam, clobazam, clonazepam, diazepam, midazolam, oxazepam, temazepam, triazolam, zopiclone, and selected metabolites in human hair and nail samples employing liquid-liquid extraction and tandem liquid chromatography-mass spectrometry (LC-MS-MS). Hair and nail samples were obtained from patients who had recently discontinued or were currently prescribed one or more of the targeted drugs. Prazepam was used as the internal standard for all compounds. Some components in the hair matrix gave the same transitions as some of the analytes but did not compromise the analyses because their retention times differed from those for the target compounds. The analytical run time was 8-10min. Results of the hair analysis of a DFSA victim are also presented.
A simple method for the quantification of tipranavir, a new non-peptidic protease-inhibitor, was developed. An internal standard, prazepam, was added to 100 microl of plasma before a liquid-liquid extraction by 3 ml of tert-butyl methyl ether. The extracts were evaporated to dryness and reconstituted with 100 microl of mobile phase before being injected in the chromatographic system. The separation was made on a C8 column using sodium acetate buffer (pH 5):methanol:acetonitrile (35:30:35, v/v/v) as mobile phase. The detection was performed at a wavelength of 260 nm. The method was linear and has been validated over a concentration range of 2-80 mg/l. The mean precision and accuracy of the method were respectively, 10.5 and -9.1%. The mean recovery was 70.8%.
Prescription and use of benzodiazepins were evaluated with a patients survey. Direct interview were conducted with 150 patients in ten pharmacies in the city of Saint-Louis, Senegal from January to June 2002. Ten of the 15 retail pharmacies in this city agreed to participate in the survey. All patients gave their agreement to participate to the study; the questionnaire contained essentially closed questions. Writers of prescriptions were general practitioners (38.67%), specialists (34.67%), nurses (18%) and midwifes (8.66%). The most prescribed benzodiazepins were prazepam, dipotassic clorazepate, lorazepam and diazepam. Use of these drugs during night is most recommended. Nevertheless, 26.67% of the prescriptions indicated the drug should be use during the day. The period of use was between one and three Months for 33.99% of patients and three Months or more in 42%. Benzodiazepins were used by 66.67% for insomnia, alone or associated with another condition, for anxiety by 14.6% and for epilepsy by 10%. Prescriptions were for benzodiazepins alone in 47.37% of the patients and in combination with other psychotropic drugs for 19.33%. Somnolence and dependence were the most reported side effects.
We describe a rapid method for precisely measuring concentrations of diazepam, oxazepam and N-desmethyldiazepam in blood by high-pressure liquid chromatography. The drugs, together with an internal standard, prazepam, are extracted from 2 ml of blood and analyzed isocratically on a reversed-phase column with a mobile phase consisting of acetonitrile-0.01 M sodium acetate buffer (35:65 v/v). The eluted drugs are detected by their absorption at 240 nm. The sensitivity of this method is 30 microgram/l for oxazepam and N-desmethyldiazepam, 40 microgram/l for diazapam, for 2-ml blood samples. Relative recovery of added drugs to blood varies from 91 to 110%. The day-to-day precision (coefficient of variation) established by 10 replicate analyses was 2.8 to 9.6%.