RESUMEN
The Japanese Pharmacopoeia (JP) is an official normative publication that is referred to, for establishing the authenticity and properties and maintaining the quality of pharmaceutics in Japan. Partial amendments are periodically made to these guidelines to keep up with the progress of science and technology, and the international harmonization is revised every 5 years. Thus, "Internationalization of the JP" is one of the more important issues to address for the revision of the JP. For example, the incorporation of the test methods that have been used in other pharmacopeias, such as the United States Pharmacopeia (USP) and the European Pharmacopoeia (EP), into the JP is a useful approach. In light of this, we have recently reported changes in test methods in the 17th JP, "Establishment of a quantitative test method for clonidine hydrochloride from using a potentiometric titration method to using HPLC". As a part of our ongoing research to change test methods for internationalization, we selected lorazepam. Lorazepam is analyzed using a potentiometric titration method as listed in the 17th JP; however, both the USP and EP use HPLC for quantitative analysis of this drug. In this study, we synthesized the related impurities of lorazepam listed in the USP and the EP and determined their purities using quantitative NMR. The separation conditions of these compounds, including lorazepam, were examined using HPLC and simultaneous analyses were performed. In addition, lorazepam extracted from the tablets was analyzed using conditions similar to those used for the analysis of the related impurities.
Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Cromatografía Líquida de Alta Presión/normas , Internacionalidad , Lorazepam/análisis , Farmacopeas como Asunto/normas , Psicotrópicos/análisis , Japón , Lorazepam/síntesis química , Lorazepam/química , Espectroscopía de Resonancia Magnética , Psicotrópicos/síntesis química , Psicotrópicos/químicaRESUMEN
The slowness of dripping and the presence of alcohol have been offered/suggested as possible causes for the increased risk of developing dependence to the oral formulation of lormetazepam rather than to other anxiolytic and hypnotic drugs. We hence assessed the time of dripping of the most used benzodiazepines and z-drugs oral solution products under experimental conditions and the different employed excipients through a comparative analysis of the Summaries of Product Characteristics. A wide range of the median overall dispensing time was found across the eight products included in the analysis. Among the products containing LMZ, Minias® ranked in the fourth position, while LMZ Mylan Generics® and Noctamid® in the sixth and third, respectively. Our data suggest that the pace of dripping and the presence of alcohol cannot be considered themselves the cause that triggered the abuse of lormetazepam. More precisely, the quantity of alcohol per bottle has been found negligible at therapeutic doses; however, when these are exceeded, they may have clinical implications for patients. Further studies are needed to assess them. Meanwhile, the public-health problem remains and some improvements should be carried out at different levels, to guarantee the appropriate prescription and use of lormetazepam oral solution.
Asunto(s)
Etanol/administración & dosificación , Hipnóticos y Sedantes/administración & dosificación , Lorazepam/análogos & derivados , Trastornos Relacionados con Sustancias/epidemiología , Administración Oral , Humanos , Hipnóticos y Sedantes/química , Lorazepam/administración & dosificación , Lorazepam/química , Factores de RiesgoRESUMEN
The present study illustrates the application of the concept of Quality by Design for development, optimization and evaluation of Lorazepam loaded microemulsion containing ion responsive In situ gelator gellan gum and carbopol 934. A novel approach involving interactions between surfactant and polymer was employed to achieve controlled drug release and reduced mucociliary clearance. Microemulsion formulated using preliminary solubility study and pseudo ternary phase diagrams showed significantly improved solubilization capacity of Lorazepam with 54.31±6.07nm droplets size. The effect of oil to surfactant/cosurfactant ratio and concentration of gelling agent on the drug release and viscosity of microemulsion gel (MEG) was evaluated using a 32 full factorial design. The gel of optimized formulation (MEG1) showed a drug release up to 6h of 97.32±1.35% of total drug loaded. The change in shear-dependent viscosity for different formulations on interaction with Simulated Nasal Fluid depicts the crucial role of surfactant-polymer interactions on the gelation properties along with calcium ions binding on the polymer chains. It is proposed that the surfactant-polymer interactions in the form of a stoichiometric hydrogen bonding between oxyethylene and carboxylic groups of the polymers used, provides exceptional ME stability and adhesion properties. Compared with the marketed formulation, optimized MEG showed improved pharmacodynamic activity. Ex vivo diffusion studies revealed significantly higher release for MEG compared to microemulsion and drug solution. MEG showed higher flux and permeation across goat nasal mucosa. According to the study, it could be concluded that formulation would successfully provide the rapid onset of action, and decrease the mucociliary clearance due to formation of in situ gelling mucoadhesive system.
Asunto(s)
Sistemas de Liberación de Medicamentos/métodos , Lorazepam/química , Administración Intranasal , Emulsiones , Humanos , Lorazepam/uso terapéuticoRESUMEN
INTRODUCTION: Many drugs are unavailable in suitable oral paediatric dosage forms, and pharmacists often have to compound drugs to provide paediatric patients with an acceptable formulation in the right dose. Liquid formulations offer the advantage of dosing flexibility and ease of administration to young patients, but drug substances often show poor aqueous solubility. The objective of this work was to study different solvents and matrices to design a liquid formulation for poorly water soluble drugs, using lorazepam as model drug. METHODS: Three different formulation strategies were explored to improve the solubility. Firstly, water-soluble organic solvents were used to improve the aqueous solubility directly, secondly, ionic surfactants were used to solubilise the model drug, and thirdly, complexation of lorazepam with cyclodextrin was studied. Specific attention was paid to excipients, adequate taste correction and palatability. For the final formulation, physical and chemical stability and microbiological quality were assessed for 12months. RESULTS: An organic solvent based formulation, containing a mixture of polyethylene glycol and glycerol 85%, with a minimum amount of propylene glycol, proved to be physically and chemically stable. Development of the non-ionic surfactants formulation was discontinued due to taste problems. The cyclodextrin formulations were physically stable, but lorazepam content declined to 90% within five months. The final formulation contained in volume concentration (%v/v) 87% glycerol, 10% polyethylene glycol 400 and 3% propylene glycol. Orange essence was the preferred taste corrector. The formulation remained stable for 12months at 4°C, with lorazepam content remaining >95%. Related substances increased during the study period but remained below 2%. In-use stability was proven up to 4weeks. CONCLUSION: An organic solvent based oral formulation was shown to be superior to a non-ionic surfactant based formulation or a cyclodextrin formulation. These results may help to formulate paediatric formulations of other poorly water soluble drugs, to aid pharmacy compounding.
Asunto(s)
Lorazepam/química , Administración Oral , Adulto , Estabilidad de Medicamentos , Aromatizantes/química , Glicerol/química , Humanos , Pediatría , Polietilenglicoles/química , Propilenglicol/química , Solubilidad , Soluciones , Agua/químicaRESUMEN
OBJECTIVE: Transportation by air exposes drugs used in emergency medical services to vibrations. The aim of the study was to determine whether or not vibrations caused by a helicopter induce the degradation of 5 drugs used in this setting. METHODS: A longitudinal study in an operating medical helicopter along with a worst case was conducted. The studied drugs were 3 drugs labeled for refrigeration (cisatracurium, lorazepam, and succinylcholine) and 2 albumin solutions (human albumin 4% and 20%). These drugs were stored for 4 months according to the following conditions: inside a helicopter, worst case with exposure to extreme vibrations, at room temperature, and according to manufacturers' recommendations. Samples were analyzed with validated high-performance liquid chromatography assay methods. A drug was considered stable if the remaining drug content was above 90% of the label claim. Except for the albumin solutions, visual inspection was used to determine instability by the formation of aggregates. RESULTS: Only the samples stored at room temperature became unstable after 4 months. No difference in extreme foaming was observed in the albumin solutions. CONCLUSIONS: These data suggest that the effect of degradation of drugs caused by vibrations is negligible. Temperature was observed as the main cause of drug degradation.
Asunto(s)
Ambulancias Aéreas , Albúminas/química , Atracurio/análogos & derivados , Lorazepam/química , Succinilcolina/química , Temperatura , Vibración , Atracurio/química , Cromatografía Líquida de Alta Presión , Estabilidad de Medicamentos , Servicios Médicos de Urgencia , Humanos , Estudios LongitudinalesRESUMEN
Chemotherapy induced nausea and vomiting is problematic for many patients undergoing chemotherapy. Multiple-drug treatments have been developed to mitigate chemotherapy induced nausea and vomiting. A patient-controlled infusion of diphenhydramine hydrochloride, lorazepam, and dexamethasone sodium phosphate has been studied in patients who are refractory to first-line therapy. Unfortunately, the physical and chemical compatibility of this three-drug combination is not available in the published literature. Chemical compatibility was evaluated using high-performance liquid chromatography with ultraviolet detection. Visual observation was employed to detect change in color, clarity, or gas evolution. Turbidity and pH measurements were performed in conjunction with visual observation at hours 0, 24, and 48. Results showed that diphenhydramine hydrochloride 4 mg/mL, lorazepam 0.16 mg/mL, and dexamethasone sodium phosphate 0.27 mg/mL in 0.9% sodium chloride stored in polypropylene syringes were compatible, and components retained greater than 95% of their original concentration over 48 hours when stored at room temperature.
Asunto(s)
Dexametasona/análogos & derivados , Difenhidramina/química , Lorazepam/química , Dexametasona/química , Estabilidad de Medicamentos , Almacenaje de Medicamentos , Polipropilenos , Cloruro de Sodio/química , JeringasRESUMEN
At least 120 non-olfactory G-protein-coupled receptors in the human genome are 'orphans' for which endogenous ligands are unknown, and many have no selective ligands, hindering the determination of their biological functions and clinical relevance. Among these is GPR68, a proton receptor that lacks small molecule modulators for probing its biology. Using yeast-based screens against GPR68, here we identify the benzodiazepine drug lorazepam as a non-selective GPR68 positive allosteric modulator. More than 3,000 GPR68 homology models were refined to recognize lorazepam in a putative allosteric site. Docking 3.1 million molecules predicted new GPR68 modulators, many of which were confirmed in functional assays. One potent GPR68 modulator, ogerin, suppressed recall in fear conditioning in wild-type but not in GPR68-knockout mice. The same approach led to the discovery of allosteric agonists and negative allosteric modulators for GPR65. Combining physical and structure-based screening may be broadly useful for ligand discovery for understudied and orphan GPCRs.
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Alcoholes Bencílicos/química , Alcoholes Bencílicos/farmacología , Descubrimiento de Drogas , Lorazepam/química , Lorazepam/farmacología , Receptores Acoplados a Proteínas G/metabolismo , Triazinas/química , Triazinas/farmacología , Regulación Alostérica/efectos de los fármacos , Sitio Alostérico , Animales , Ansiolíticos/análisis , Ansiolíticos/química , Ansiolíticos/metabolismo , Ansiolíticos/farmacología , Alcoholes Bencílicos/análisis , Alcoholes Bencílicos/metabolismo , Condicionamiento Clásico , Miedo , Femenino , Células HEK293 , Humanos , Ligandos , Lorazepam/análisis , Lorazepam/metabolismo , Masculino , Memoria/efectos de los fármacos , Ratones , Ratones Noqueados , Modelos Moleculares , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/antagonistas & inhibidores , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/deficiencia , Transducción de Señal/efectos de los fármacos , Triazinas/análisis , Triazinas/metabolismoRESUMEN
The aim of the present study was to optimize lorazepam loaded PLGA nanoparticles (Lzp-PLGA-NPs) by investigating the effect of process variables on the response using Box-Behnken design. Effect of four independent factors, that is, polymer, surfactant, drug, and aqueous/organic ratio, was studied on two dependent responses, that is, z-average and % drug entrapment. Lzp-PLGA-NPs were successfully developed by nanoprecipitation method using PLGA as polymer, poloxamer as surfactant and acetone as organic phase. NPs were characterized for particle size, zeta potential, % drug entrapment, drug release behavior, TEM, and cell viability. Lzp-PLGA-NPs were characterized for drug polymer interaction using FTIR. The developed NPs showed nearly spherical shape with z-average 167-318 d·nm, PDI below 0.441, and -18.4 mV zeta potential with maximum % drug entrapment of 90.1%. In vitro drug release behavior followed Korsmeyer-Peppas model and showed initial burst release of 21.7 ± 1.3% with prolonged drug release of 69.5 ± 0.8% from optimized NPs up to 24 h. In vitro drug release data was found in agreement with ex vivo permeation data through sheep nasal mucosa. In vitro cell viability study on Vero cell line confirmed the safety of optimized NPs. Optimized Lzp-PLGA-NPs were radiolabelled with Technitium-99m for scintigraphy imaging and biodistribution studies in Sprague-Dawley rats to establish nose-to-brain pathway.
Asunto(s)
Química Farmacéutica , Lorazepam/administración & dosificación , Nanopartículas/administración & dosificación , Estado Epiléptico/tratamiento farmacológico , Administración Intranasal , Animales , Sistemas de Liberación de Medicamentos , Humanos , Lorazepam/química , Nanopartículas/química , Mucosa Nasal/efectos de los fármacos , Tamaño de la Partícula , Polímeros/administración & dosificación , Polímeros/química , Ratas , Ovinos , Estado Epiléptico/patología , Distribución TisularRESUMEN
INTRODUCTION: EMS treatment of status epilepticus improves outcomes, but the benzodiazepine best suited for EMS use is unclear, given potential high environmental temperature exposures. OBJECTIVE: To describe the degradation of diazepam, lorazepam, and midazolam as a function of temperature exposure and time over 120 days of storage on active EMS units. METHODS: Study boxes containing vials of diazepam, lorazepam, and midazolam were distributed to 4 active EMS units in each of 2 EMS systems in the southwestern United States during May-August 2011. The boxes logged temperature every minute and were stored in EMS units per local agency policy. Two vials of each drug were removed from each box at 30-day intervals and underwent high-performance liquid chromatography to determine drug concentration. Concentration was analyzed as mean (and 95%CI) percent of initial labeled concentration as a function of time and mean kinetic temperature (MKT). RESULTS: 192 samples were collected (2 samples of each drug from each of 4 units per city at 4 time-points). After 120 days, the mean relative concentration (95%CI) of diazepam was 97.0% (95.7-98.2%) and of midazolam was 99.0% (97.7-100.2%). Lorazepam experienced modest degradation by 60 days (95.6% [91.6-99.5%]) and substantial degradation at 90 days (90.3% [85.2-95.4%]) and 120 days (86.5% [80.7-92.3%]). Mean MKT was 31.6°C (95%CI 27.1-36.1). Increasing MKT was associated with greater degradation of lorazepam, but not midazolam or diazepam. CONCLUSIONS: Midazolam and diazepam experienced minimal degradation throughout 120 days of EMS deployment in high-heat environments. Lorazepam experienced significant degradation over 120 days and appeared especially sensitive to higher MKT exposure.
Asunto(s)
Diazepam/química , Servicios Médicos de Urgencia/métodos , Calor/efectos adversos , Lorazepam/química , Análisis de Varianza , Benzodiazepinas/administración & dosificación , Benzodiazepinas/química , Diazepam/administración & dosificación , Estabilidad de Medicamentos , Almacenaje de Medicamentos , Humanos , Modelos Lineales , Lorazepam/administración & dosificación , Midazolam/administración & dosificación , Midazolam/química , Medición de Riesgo , Muestreo , Sensibilidad y Especificidad , Estado Epiléptico/tratamiento farmacológico , Factores de TiempoRESUMEN
This manuscript reports on the study of Lorazepam (LZP) phototransformation pathways under artificial UV and natural solar irradiation, through photolytic and TiO2-assisted photocatalytic processes. Three experimental set-ups were employed: two lab-scale photoreactors, each provided with an UV lamp (one medium pressure mercury lamp and one blacklight blue lamp), and a pilot-scale Solar Plant with Compound Parabolic Collectors (CPCs). Samples collected along the different phototreatment experiments were analyzed by ultra-high performance liquid chromatography-quadrupole-time-of-flight-mass spectrometry (UHPLC/QqToF-MS). The key assumption of the analytical approach was that related compounds (LZP and its by-products (LBPs)) provide identical "diagnostic fragment ions". Identification was also based on the chlorine atoms specific isotopic pattern, as well as accurate masses. Six major LBPs were identified and elucidated, with nominal [M + H](+) masses of 337, 303, 319, 275, 291 and 293 Da. The proposed LZP photodegradation mechanism included the initial opening of the diazepinone seven-membered ring, followed by a rearrangement into a highly stabilized six-membered aromatic ring and subsequent cleavage and/or hydroxylation reactions. The evolution profiles of LBPs were described for each of the three experimental prototypes and the CPCs Solar Pilot Plant proved to be the most efficient one. Finally, LZP photocatalytic degradation was further assessed on a municipal effluent, where the photoproducts generated showed to be more persistent than LZP itself.
Asunto(s)
Lorazepam/química , Fotólisis , Titanio/química , Contaminantes Químicos del Agua/química , Catálisis , CinéticaRESUMEN
The widely used hypnosedative-anxiolytic agent R,S-lorazepam is cleared predominantly by conjugation with glucuronic acid in humans, but the enantioselective glucuronidation of lorazepam has received little attention. The present study characterized the kinetics of the separate R and S enantiomers of lorazepam by human liver microsomes (HLMs) and by a panel of recombinant human UDP-glucuronosyltransferase (UGT) enzymes. Respective mean K(m) and V(max) values for R- and S-lorazepam glucuronidation by HLM were 29 ± 8.9 and 36 ± 10 µM, and 7.4 ± 1.9 and 10 ± 3.8 pmol/min â mg. Microsomal intrinsic clearances were not significantly different, suggesting the in vivo clearances of R- and S-lorazepam are likely to be similar. Both R- and S-lorazepam were glucuronidated by UGT2B4, 2B7, and 2B15, whereas R-lorazepam was additionally metabolized by the extrahepatic enzymes UGT1A7 and 1A10. Based on in vitro clearances and consideration of available in vivo and in vitro data, UGT2B15 is likely to play an important role in the glucuronidation of R- and S-lorazepam. However, the possible contribution of other enzymes and the low activities observed in vitro indicate that the lorazepam enantiomers are of limited use as substrate probes for UGT2B15. To identify potential drug-drug interactions, codeine, fluconazole, ketamine, ketoconazole, methadone, morphine, valproic acid, and zidovudine were screened as inhibitors of R- and S-lorazepam glucuronidation by HLM. In vitro-in vivo extrapolation suggested that, of these drugs, only ketoconazole had the potential to inhibit lorazepam clearance to a clinically significant extent.
Asunto(s)
Glucurónidos/metabolismo , Glucuronosiltransferasa/antagonistas & inhibidores , Glucuronosiltransferasa/metabolismo , Lorazepam/metabolismo , Microsomas Hepáticos/metabolismo , Interacciones Farmacológicas/fisiología , Inhibidores Enzimáticos/metabolismo , Inhibidores Enzimáticos/farmacología , Femenino , Glucurónidos/química , Humanos , Lorazepam/química , Masculino , Microsomas Hepáticos/efectos de los fármacos , Preparaciones Farmacéuticas/administración & dosificación , Preparaciones Farmacéuticas/química , Preparaciones Farmacéuticas/metabolismo , EstereoisomerismoRESUMEN
BACKGROUND: The choice of the optimal benzodiazepine to treat prehospital status epilepticus is unclear. Lorazepam is preferred in the emergency department, but concerns about nonrefrigerated storage limits emergency medical services (EMS) use. Midazolam is increasingly popular, but its heat stability is undocumented. OBJECTIVE: This study evaluated temperature-dependent degradation of lorazepam and midazolam after 60 days in the EMS environment. METHODS: Lorazepam or midazolam samples were collected prior to (n = 139) or after (n = 229) 60 days of EMS deployment during spring-summer months in 14 metropolitan areas across the United States. Medications were stored in study boxes that logged temperature every minute and were stored in EMS units per local agency policy. Mean kinetic temperature (MKT) exposure was derived for each sample. Drug concentrations were determined in a central laboratory by high-performance liquid chromatography. Concentration as a function of MKT was analyzed by linear regression. RESULTS: Prior to deployment, measured concentrations of both benzodiazepines were 1.0 relative to labeled concentration. After 60 days, midazolam showed no degradation (mean relative concentration 1.00, 95% confidence interval [CI] 1.00-1.00) and was stable across temperature exposures (adjusted R(2) -0.008). Lorazepam experienced little degradation (mean relative concentration 0.99, 95% CI 0.98-0.99), but degradation was correlated to increasing MKT (adjusted R(2) 0.278). The difference between the temperature dependence of degradation of midazolam and lorazepam was statistically significant (T = -5.172, p < 0.001). CONCLUSIONS: Lorazepam experiences small but statistically significant temperature-dependent degradation after 60 days in the EMS environment. Additional study is needed to evaluate whether clinically significant deterioration occurs after 60 days. Midazolam shows no degradation over this duration, even in high-heat conditions.
Asunto(s)
Servicios Médicos de Urgencia/normas , Lorazepam/química , Midazolam/química , Estado Epiléptico/tratamiento farmacológico , Anticonvulsivantes/química , Anticonvulsivantes/uso terapéutico , Cromatografía Líquida de Alta Presión , Estabilidad de Medicamentos , Almacenaje de Medicamentos/métodos , Almacenaje de Medicamentos/normas , Humanos , Modelos Lineales , Lorazepam/uso terapéutico , Midazolam/uso terapéutico , Estudios Multicéntricos como Asunto , Uso Fuera de lo Indicado , Ensayos Clínicos Controlados Aleatorios como Asunto , Temperatura , Estados UnidosRESUMEN
Benzodiazepine (lorazepam, estazolam, chlordiazepoxide, and ketazolam) stability was studied in postmortem blood, bile, and vitreous humor stored at different temperatures over six months. The influence of NaF, in blood and bile samples, was also investigated. A solid-phase extraction technique was used on all the studied samples, and benzodiazepine quantification was performed by high-performance liquid chromatography-diode-array detection. Benzodiazepine concentration remained almost stable in all samples stored at -20°C and -80°C. Estazolam appeared to be a stable benzodiazepine during the six-month study, and ketazolam proved to be the most unstable benzodiazepine. A 100% loss of ketazolam occurred in all samples stored over 1 or 2 weeks at room temperature and over 8 or 12 weeks at 4°C, with the simultaneous detection of diazepam. Chlordiazepoxide suffered complete degradation in all samples, except preserved bile samples, stored at room temperature. Samples stored at 4°C for 6 months had a 29-100% decrease in chlordiazepoxide concentration. The data obtained suggest that results from samples with these benzodiazepines stored long-term should be cautiously interpreted. Bile and vitreous humor proved to be the most advantageous samples in cases where degradation of benzodiazepines by microorganisms may occur.
Asunto(s)
Benzodiazepinas/química , Benzodiazepinas/análisis , Clordiazepóxido/análisis , Clordiazepóxido/química , Estabilidad de Medicamentos , Estazolam/análisis , Estazolam/química , Humanos , Lorazepam/análisis , Lorazepam/química , Extracción en Fase Sólida , TemperaturaRESUMEN
Lorazepam is a strong sedative for intensive care patients and a commonly used method of administering it to the patient is by infusion of a freshly prepared lorazepam solution. During lorazepam infusion often unwanted lorazepam crystallization occurs, resulting in line obstruction and reduced lorazepam concentrations. With the aid of solubility measurements a solid-liquid phase diagram for lorazepam in mixtures of a commercially available lorazepam solution and an aqueous glucose solution was determined. This confirmed that the glucose solution acts as an anti-solvent, greatly reducing the lorazepam solubility in the infusion solution. Three approaches are proposed to obtain stable lorazepam solutions upon mixing both solutions and thus to prevent crystallization during infusion: (1) using a high lorazepam concentration, and thus a lower glucose solution volume fraction, in the mixed solution; (2) using an elevated temperature during solution preparation and administration; (3) reducing the lorazepam concentration in the commercial lorazepam solution.
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Glucosa/química , Hipnóticos y Sedantes/química , Soluciones Isotónicas/química , Lorazepam/química , Cristalización , Calor , Infusiones Intravenosas , Solubilidad , JeringasRESUMEN
As several sedative-hypnotics are distributed illegally and are available domestically through media like the internet, their abuse is becoming a serious social problem. In the present study, four legal cases involving abuse of diazepam, midazolam, and/or zolpidem were proved by hair analysis using a simultaneous quantification method for the determination of diazepam (and its metabolites), lorazepam, midazolam, and zolpidem, which are often illegally abused in Korea, in hair that was developed and validated. Drugs and metabolites in hair were extracted using methanol followed by solid-phase extraction. The extracts were derivatized with N-methyl-N-(trimethylsilyl)trifluoroacetamide (MSTFA) and analyzed using gas chromatography-mass spectrometry in selected ion monitoring mode. The validation parameters of the method, including selectivity, linearity, limits of detection and quantification (LOQ), recovery, intra- and interassay precision and accuracy, and processed sample stability, were satisfactory. Moreover, the developed method was successfully applied to actual cases. In case 1, which involved a pop singer who was detained for suspected drug abuse, the concentrations of diazepam and nordiazepam were 5.7 and 2.0 ng/mg in nonpigmented hair and 6.6 and 1.8 ng/mg in pigmented hair, respectively. In case 2, 0.4 ng/mg zolpidem was detected in hair from a drug abuser who purchased illegally through the internet, and 0.2 ng/mg midazolam was detected in hair from an illegal drug seller in case 3. In case 4, diazepam (lower than the LOQ), nordiazepam (0.7 ng/mg), and zolpidem (0.7 ng/mg) were detected in hair from a medical doctor who abused drugs using forged prescriptions.
Asunto(s)
Cabello/química , Hipnóticos y Sedantes/análisis , Drogas Ilícitas/análisis , Detección de Abuso de Sustancias/métodos , Adulto , Diazepam/análisis , Diazepam/química , Cromatografía de Gases y Espectrometría de Masas , Humanos , Hipnóticos y Sedantes/química , Drogas Ilícitas/química , Límite de Detección , Lorazepam/análisis , Lorazepam/química , Masculino , Midazolam/análisis , Midazolam/química , Persona de Mediana Edad , Piridinas/análisis , Piridinas/química , Adulto Joven , ZolpidemRESUMEN
BACKGROUND: A fast and sensitive assay for quantifying total and unbound concentrations of lorazepam (Lzp), oxazepam (Ozp) and temazepam (Tzp) in human plasma was needed for a plasma protein binding study. RESULTS: Plasma samples were precipitated with acetonitrile for determination of total concentrations or subjected to ultrafiltration for determination of unbound concentrations. An LC-MS/MS assay was developed with an Allure® PFP propyl column and a mobile phase of 35% acetonitrile/0.1% formic acid over 4.5 min and ESI+-MS/MS detection. Matrix effects were negligible in plasma and approximately 70% in ultrafiltrate but were accounted for by the internal standards Lzp-d4, Ozp-d5 and Tzp-d5. The assay was validated for total concentrations of 10-100 ng/ml Lzp, 200-2000 ng/ml Ozp and 100-1000 ng/ml Tzp, and for unbound concentrations of 1-10 ng/ml Lzp, 20-200 ng/ml Ozp and 10-100 ng/ml Tzp. Precision was <14% CV and accuracy was 96-110% throughout the calibration range. The mean precision of triplicate analysis of 60 study samples was <4% CV for total and <8% CV for unbound concentrations. CONCLUSION: A fast and sensitive assay was developed and validated. It has been applied successfully to a protein binding study.
Asunto(s)
Ansiolíticos/sangre , Lorazepam/sangre , Oxazepam/sangre , Temazepam/sangre , Ansiolíticos/química , Ansiolíticos/normas , Calibración , Cromatografía Liquida , Hemofiltración , Humanos , Lorazepam/química , Lorazepam/normas , Oxazepam/química , Oxazepam/normas , Espectrometría de Masas en Tándem , Temazepam/química , Temazepam/normasRESUMEN
The inclusion of hyperspectral imaging systems in the manufacturing and development of pharmaceutical products is allowing a successful improvement in the quality control of solid dosage forms. The correct distribution not only of active pharmaceutical ingredient (API) but also of the rest of excipients is essential to assure the correct behavior of the tablet when ingested. This is especially relevant in tablets with low content of potent APIs, in which the prescribed intake dosage frequently corresponds to half-a-tablet. Therefore, the aim of this work is to study the surface distribution of the compounds in tablets with low API content. The proposed procedure includes the scanning of the tablet surface using near infrared hyperspectral spectroscopy in association with multivariate curve resolution (MCR) techniques to obtain selective pictures for each individual compound and to allow the fast assessment of their distribution in the measured surface. As an example, a set of commercial Lorazepam tablets (approximately 1% mass fraction of API, and four excipients) were analyzed. The results obtained show the capacity of the proposed methodology as an expedite approach to evaluate the uniformity of the contents between and within tablets. A method to estimate the homogeneity distribution of API in the two halves of the tablet is also proposed.
Asunto(s)
Ansiolíticos/química , Excipientes/química , Lorazepam/química , Preparaciones Farmacéuticas/análisis , Espectroscopía Infrarroja Corta/métodos , Ansiolíticos/análisis , Celulosa/análisis , Celulosa/química , Simulación por Computador , Excipientes/análisis , Excipientes/síntesis química , Lactosa/análisis , Lactosa/química , Lorazepam/análisis , Ensayo de Materiales , Almidón/análogos & derivados , Almidón/análisis , Almidón/síntesis química , Almidón/química , Ácidos Esteáricos/análisis , Ácidos Esteáricos/síntesis química , Ácidos Esteáricos/química , Propiedades de Superficie , ComprimidosRESUMEN
A particle engineering method that adsorbs a microfine vinyl polymer coat to crystalline drug microparticles has been shown to be an effective way to control delivery. However, the means by which the functional performance of such microparticles is altered by the behaviour of the polymers in the microparticle coat remains unclear. The aim of this study was to determine the influence of vinyl polymer coating on the in vitro delivery characteristics of intranasal lorazepam microparticles. A series of four, similarly sized (ca. 10 µm), lorazepam-rich microparticles with different polymer coats were generated. The absorption of the polymer coats appeared to disrupt lorazepam solid state dimer formation in the microparticles, which manifested in a reduction in drug melting point. Mildly cohesive particles (aerodynamic diameter of 32 µm) that allowed rapid drug release (ca. 80% in 5 min) were generated when partially hydrolysed PVA dominated the microparticle coat, whilst fully hydrolysed PVA reduced particle cohesion and retarded drug release (ca. 15% release in 5 min). Infrared analysis showed that the properties of the microparticles were dictated by the strength of the hydrogen bonding in the polymer coat and not the strength of coat adsorption that was facilitated by hydrogen bond formation between the hydroxyl groups of the PVA and the hydroxyl group at position C3 of the lorazepam diazepine ring.
Asunto(s)
Sistemas de Liberación de Medicamentos , Excipientes/química , Hipnóticos y Sedantes/administración & dosificación , Lorazepam/administración & dosificación , Administración Intranasal , Cristalización , Enlace de Hidrógeno , Hipnóticos y Sedantes/química , Hipnóticos y Sedantes/farmacocinética , Lorazepam/química , Lorazepam/farmacocinética , Pulmón/metabolismo , Microesferas , Tamaño de la Partícula , Alcohol Polivinílico/química , Povidona/química , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura de TransiciónRESUMEN
INTRODUCTION: Many different types of benzodiazepine medications exist to treat a wide array of psychological and physical diseases based on dosage and implications. Benzodiazepines are generally considered as safe and effective drugs in short term; however, cognitive impairments and paradoxical effects occasionally occur. Our recent studies have shown that some 1,4-benzodiazepines exhibit cytogenetic activity (alprazolam, diazepam, and lorazepam) in normal human lymphocyte cultures. 1,5-Benzodiazepine derivatives are used in the synthesis of fused ring compounds, to study the chemical structure-pharmacological activity correlation. We synthesized four compounds of this category with small structural differences. AIM: The aim of this study was to investigate their cytogenetic activity in vitro at doses equivalent to the per os doses of the used 1,4-benzodiazepines. Sister chromatid exchanges (SCEs), proliferation rate index, and mitotic index were evaluated in lymphocytes of peripheral blood cultures from two healthy donors. RESULTS: Three of the newly synthesized compounds exhibited positive cytogenetic activity (statistically significant reduction of SCEs, p < 0.01, t-test), without showing cytostatic properties. CONCLUSION: The observed reduction of the lymphocytes' SCEs because of 1,5-benzodiazepines' activity is remarkable and requires further investigation to improve pharmacological effects.