Prolonged Zaleplon Treatment Increases the Expression of Proteins Involved in GABAergic and Glutamatergic Signaling in the Rat Hippocampus.

Zaleplon is a positive allosteric modulator of the γ-aminobutyric acid (GABA)A receptor approved for the short-term treatment of insomnia. Previous publications on zaleplon have not addressed the proteins involved in its mechanism of action but have mostly referred to behavioral or pharmacological studies. Since both GABAergic and glutamatergic signaling have been shown to regulate wakefulness and sleep, we examined the effects of prolonged zaleplon treatment (0.625 mg/kg for 5 days) on these systems in the hippocampus of male Wistar rats. Western blot and immunohistochemical analyses showed that the upregulated components of GABAergic signaling (glutamate decarboxylase, vesicular GABA transporter, GABA, and α1 subunit of the GABAA receptor) were accompanied by increased protein levels in the glutamatergic system (vesicular glutamate transporter 1 and NR1, NR2A, and NR2B subunits of N-methyl-d-aspartate receptor). Our results, showing that zaleplon enhances GABA neurotransmission in the hippocampus, were not surprising. However, we found that treatment also increased glutamatergic signaling. This could be the result of the downregulation of adenosine A1 receptors, important modulators of the glutamatergic system. Further studies are needed to investigate the effects of the zaleplon-induced increase in hippocampal glutamatergic neurotransmission and the possible involvement of the adenosine system in zaleplon's mechanism of action.

[Measurement of benzodiazepine receptor agonists metabolites and their concentration in urine]. / Opredelenie metabolitov agonistov benzodiazepinovykh retseptorov i ustanovlenie ikh protsentnogo soderzhaniya v moche.

The study objective was to detect and measure the ratio of metabolites of benzodiazepine receptor agonists in urine during forensic chemical and chemical and toxicological studies, as well as to characterize the main metabolites to use them to confirm the oral intake of the test substances. Data on the presence of metabolites in the urine will allow us to reliably confirm the intake of zaleplon, zopiclone, clobazam, and phenazepam and determine the routes of administration (intake) into the body of the victim. Benzodiazepine derivatives (clobazam and phenazepam) and non-benzodiazepines (zaleplon and zopiclone) have different chemical structures and similar mechanisms of action resulting in a similar clinical presentation of side effects and the need for forensic chemical study according to poisoning symptoms. Metabolites of benzodiazepine receptor agonists and their ratio in urine after oral administration were measured: zaleplon (parent compound), deethylzaleplon, 5-oxozaleplon, 5-oxodeethylzaleplon, oxozaleplon glucuronide; zopiclone (parent compound), zopiclone-N-oxide, N-desmethylzopiclone; clobazam (parent compound), N-desmethylclobazam, 4-hydroxyclobazam, hydroxydesmethylclobazam; phenazepam (parent compound) and 3-hydroxyphenazepam. It is advisable to determine zaleplon in urine by the presence of 5-oxaleplon (97% of the total amount of metabolites), zopiclone by zopiclone-N-oxide (86% in urine), clobazam by the parent compound (61% in urine), phenazepam by the parent compound (90-100% in urine).

Rapid oral transmucosal delivery of zaleplon-lavender oil utilizing self-nanoemulsifying lyophilized tablets technology: development, optimization and pharmacokinetic evaluation.

Based on the administration convenience, transmucosal buccal drug delivery allows special strength points over peroral routes for systemic delivery. It could achieve local or systemic effect and boost drugs' bioavailability for agents with first pass metabolism. The current study aimed to manufacture and optimize a lavender oil-based nanoemulsion loaded with zaleplon and incorporate it into fast-disintegrating tablets to promote its dissolution and oral bioavailability via oral mucosa. Zaleplon-loaded nanoemulsions were devised with various levels of lavender oil (10% to 25%), the surfactant Sorbeth-20 (35% to 65%), and the co-surfactant HCO-60 (20% to 40%); the extreme vertices mixture statistical design was adopted. The droplet size and drug-loading efficiency were the evaluated. The optimal formulation was transformed into self-nanoemulsified lyophilized tablets (ZP-LV-SNELTs), which were tested for their uniformity of content, friability, and disintegration time with in-vitro release. Finally, the pharmacokinetic parameters of the ZP-LV-SNELTs were determined and compared with those of marketed formulations. The optimal nanoemulsion had a droplet size of 87 nm and drug-loading capacity of 185 mg/mL. ZP-LV-SNELTs exhibited acceptable friability and weight uniformity and a short disintegration time. The in-vitro release of ZP-LV-SNELTs was 17 times faster than that of the marketed tablet. Moreover, the optimal ZP-LV-SNELTs increased the bioavailability of zaleplon in rabbits by 1.6-fold compared with the commercial tablets. Hence, this investigation revealed that ZP-LV-SNELTs delivered zaleplon with enhanced solubility, a fast release, and boosted bioavailability thru oral mucosa which provided a favorable route for drug administration which is suggested to be clinically investigated in future studies.

[Determination of zaleplon and clobazam by high performance liquid chromatography - high resolution tandem mass spectrometry using Orbitrap technology]. / Opredelenie zaleplona i klobazama metodom vysokoeffektivnoi zhidkostnoi khromatografii ­ tandemnoi mass-spektrometrii s vysokim razresheniem s ispol'zovaniem tekhnologii Orbitrap.

THE AIM OF THE STUDY: Was to develop a method for the qualitative and quantitative determination of benzodiazepine receptor agonists (zaleplon and clobazam), taking into account different chemical structures, by high-performance liquid chromatography-high-resolution tandem mass spectrometry using Orbitrap technology for the purposes and tasks of forensic medical examination. A method has been developed for the identification and quantitative determination of zaleplon and clobazam by high-performance liquid chromatography-high-resolution tandem mass spectrometry using Orbitrap technology. The proposed identification method can be used in the future to form a database of domestic mass spectra for potent and narcotic substances.

Treatment of Insomnia with Zaleplon in HIV+ Significantly Improves Sleep and Depression.

More than 50% of individuals who are HIV positive report insomnia, which can reduce HIV treatment adherence, impair quality of life, and contribute to metabolic dysfunction. Major depressive disorder is also highly comorbid in this population, leading to further impairment. There is evidence that treating insomnia may improve not only sleep, but depression and metabolic function, as well. The present study aimed to examine the effects of pharmacotherapeutic treatment of insomnia on sleep, depression, and metabolic functioning in individuals with HIV. 20 individuals with asymptomatic seropositive HIV and comorbid insomnia and depression were administered zaleplon for 6 weeks. Insomnia severity was assessed using the Insomnia Severity Index and Epworth Sleepiness Scale, and depression severity was assessed using the Quick Inventory of Depression, both prior to treatment and 6 weeks post treatment. Metabolomic changes were assessed using a comprehensive platform measuring ~2000 lipid features and polar metabolites. Linear mixed effects models demonstrated that 6 weeks of treatment with zaleplon significantly improved symptoms of both insomnia and depression. Metabolomic analyses also demonstrated that changes in insomnia severity were associated with significant changes in key branched chain amino acid metabolites. Our results show that improvement in insomnia is associated with reduced depressive symptoms and beneficial metabolomic changes. Additionally, changes in key branched chain amino acid metabolites following treatment may serve as useful biomarkers of treatment response.

The effect of non-benzodiazepine sedative hypnotics on CPAP adherence in patients with OSA: a systematic review and meta-analysis.

STUDY OBJECTIVES: This meta-analysis aimed to explore the effect of non-benzodiazepine sedative hypnotics (NBSH) on continuous positive airway pressure (CPAP) adherence in patients with obstructive sleep apnea (OSA). METHODS: We conducted a systematic search through PubMed, Medline, the Cochrane Library, EMBASE, Scopus and ClinicalTrials (all searched from inception to August 15, 2020). Publications were limited to articles, clinical conferences and letters, including randomized controlled trials and retrospective studies. We used a random-effects model to calculate the odds ratio (OR) and mean difference (MD) with corresponding confidence interval (CI). Subgroup analyses were conducted to analyze the sources of heterogeneity. RESULTS: Eight studies fulfilled the inclusion and exclusion criteria for patients newly diagnosed with obstructive sleep apnea. Overall, the use of NBSH was associated with increased use of CPAP per night (MD = 0.62 h; 95% CI = 0.26-0.98) and use for more nights (MD = 12.08%; 95% CI = 5.27-18.88). When a study seriously affecting heterogeneity was removed, more patients adhered well with CPAP use (pooled OR = 2.48; 95% CI = 1.75-3.52) with good adherence defined as CPAP use for >4 h/night on >70% of nights. Among prescribed NBSHs, eszopiclone showed the most significant effect on CPAP adherence. CONCLUSION: CPAP adherence may increase in OSA patients treated with non-benzodiazepine sedative hypnotics especially eszopiclone. The effect of zolpidem and zaleplon on CPAP adherence requires further investigation by larger scale, randomized, controlled trials.

Non-benzodiazepine hypnotic use for sleep disturbance in people aged over 55 years living with dementia: a series of cohort studies.

BACKGROUND: Sleep disturbance affects around 60% of people living with dementia and can negatively affect their quality of life and that of their carers. Hypnotic Z-drugs (zolpidem, zopiclone and zaleplon) are commonly used to treat insomnia, but their safety and efficacy have not been evaluated for people living with dementia. OBJECTIVES: To estimate the benefits and harms of Z-drugs in people living with dementia with sleep disturbance. DESIGN: A series of observational cohort studies using existing data from (1) primary care linked to hospital admission data and (2) clinical cohort studies of people living with dementia. DATA SOURCES: Primary care study - Clinical Practice Research Datalink linked to Hospital Episode Statistics and Office for National Statistics mortality data. Clinical cohort studies - the Resource Use and Disease Course in Dementia - Nursing Homes (REDIC) study, National Alzheimer's Coordinating Centre (NACC) clinical data set and the Improving Well-being and Health for People with Dementia (WHELD) in nursing homes randomised controlled trial. SETTING: Primary care study - 371 primary care practices in England. Clinical cohort studies - 47 nursing homes in Norway, 34 Alzheimer's disease centres in the USA and 69 care homes in England. PARTICIPANTS: Primary care study - NHS England primary care patients diagnosed with dementia and aged > 55 years, with sleep disturbance or prescribed Z-drugs or low-dose tricyclic antidepressants, followed over 2 years. Clinical cohort studies - people living with dementia consenting to participate, followed over 3 years, 12 years and 9 months, for REDIC, NACC and WHELD, respectively. INTERVENTIONS: The primary exposure was prescription or use of Z-drugs. Secondary exposures included prescription or use of benzodiazepines, low-dose tricyclic antidepressants and antipsychotics. MAIN OUTCOME MEASURES: Falls, fractures, infection, stroke, venous thromboembolism, mortality, cognitive function and quality of life. There were insufficient data to investigate sleep disturbance. RESULTS: The primary care study and combined clinical cohort studies included 6809 and 18,659 people living with dementia, with 3089 and 914 taking Z-drugs, respectively. New Z-drug use was associated with a greater risk of fractures (hazard ratio 1.40, 95% confidence interval 1.01 to 1.94), with risk increasing with greater cumulative dose (p = 0.002). The hazard ratio for Z-drug use and hip fracture was 1.59 (95% confidence interval 1.00 to 2.53) and for mortality was 1.34 (95% confidence interval 1.10 to 1.64). No excess risks of falls, infections, stroke or venous thromboembolism were detected. Z-drug use also did not have an impact on cognition, neuropsychiatric symptoms, disability or quality of life. LIMITATIONS: Primary care study - possible residual confounding because of difficulties in identifying patients with sleep disturbance and by dementia severity. Clinical cohort studies - the small numbers of people living with dementia taking Z-drugs and outcomes not necessarily being measured before Z-drug initiation restricted analyses. CONCLUSIONS: We observed a dose-dependent increase in fracture risk, but no other harms, with Z-drug use in dementia. However, multiple outcomes were examined, increasing the risk of false-positive findings. The mortality association was unlikely to be causal. Further research is needed to confirm the increased fracture risk. Decisions to prescribe Z-drugs may need to consider the risk of fractures, balanced against the impact of improved sleep for people living with dementia and that of their carers. Our findings suggest that when Z-drugs are prescribed, falls prevention strategies may be needed, and that the prescription should be regularly reviewed. FUTURE WORK: More research is needed on safe and effective management strategies for sleep disturbance in people living with dementia. STUDY REGISTRATION: This study is registered as European Union electronic Register of Post-Authorisation Studies (EU PAS) 18006. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 1. See the NIHR Journals Library website for further project information.

WHAT WAS THE PROBLEM?: Poor sleep is common in people living with dementia. It can worsen their own and their carer's quality of life. Sleeping tablets called Z-drugs (zolpidem, zopiclone and zaleplon) are often given to people with dementia. Some studies suggest that Z-drugs may be harmful, but no studies have looked into the effects of Z-drugs for people with dementia. Good sleep is important, but we need to understand if Z-drugs cause harm. WHAT DID WE DO?: Using existing medical records, we compared the quality of life, memory and number of falls, infections, strokes, broken bones and deaths for a group of people living with dementia taking a Z-drug, with those for a group not taking any sleep drug. WHAT DID WE FIND?: Z-drug users were no more likely to suffer falls, infection or stroke, but they were more likely to break a bone. We also found that Z-drug users died earlier, but we could not be sure that this was as a result of taking the Z-drug. Using Z-drugs did not appear to affect quality of life or memory. We talked to carers and health-care practitioners, who told us that decisions about Z-drugs need to balance a range of complicated health and social factors. WHAT DOES THIS MEAN?: We found that people living with dementia who take Z-drugs are more likely to break a bone or to die sooner than similar people with dementia who are not taking Z-drugs. However, we cannot be certain that these problems are caused by Z-drugs, as many other factors can also lead to broken bones and death. Further work is needed to clarify the risk of broken bones, but if sleep problems can be managed in other ways then this may be preferable. Patients and family carers should be involved in decisions about Z-drugs, so that they can balance the possible harms against the benefits.

The potential of intranasal delivery of nanocrystals in powder form on the improvement of zaleplon performance: in-vitro, in-vivo assessment.

OBJECTIVE: The present work focuses on improving zaleplon (ZAP) performance through nanosizing its insoluble particles which were then delivered intranasally in powder form. SIGNIFICANCE: Since nanopowders have an exceptional ability to cross cell membrane, their absorption is facilitated in the solid form. Hence, delivering insoluble ZAP nanocrystals (NC) through intranasal route improves its bioavailability due to both nanosization and the escape of hepatic metabolism. METHODS: Nanocrystals were prepared by anti-solvent precipitation followed by probe sonication in presence of Soluplus®, Poloxamer-188 (0.25%), sodium lauryl sulfate (0.5%), and mannitol. Physicochemical evaluation of the prepared NC was done by DSC and XRPD. TGA was performed for stability detection. Ex vivo permeation study through isolated cattle nasal mucosal membrane, in addition to an in vivo bioavailability study was performed for assessment of the prepared NC. RESULTS: Nanosization to 200 nm contributed to the enhancement in dissolution ∼100% within 30 min and reduced half-life to 1.63 min. Confirmation of adsorption of polymers over NC' surface was elucidated. TGA confirmed their thermal stability. Ex vivo permeation study showed a 2.7 enhancement ratio in favor of the prepared NC. Both the extent and rate of NC absorption through nasal mucosa of rabbits were significantly higher (p Ë‚ .05) than in case of oral tablets. The relative bioavailability of NC was increased 3.14 times as compared to the Sleep aid® tablets. CONCLUSION: The intranasal delivery of nanoscale ZAP powder proved to be a successful alternative to oral formulations that suffer poor absorption and limited bioavailability.

Polymeric nanoencapsulation of zaleplon into PLGA nanoparticles for enhanced pharmacokinetics and pharmacological activity.

Zaleplon (ZP) is a sedative and hypnotic drug used for the treatment of insomnia. Despite its potent anticonvulsant activity, ZP is not commonly used for the treatment of convulsion since ZP is characterized by its low oral bioavailability as a result of poor solubility and extensive liver metabolism. The following study aimed to formulate specifically controlled release nano-vehicles for oral and parenteral delivery of ZP to enhance its oral bioavailability and biological activity. A modified single emulsification-solvent evaporation method of sonication force was adopted to optimize the inclusion of ZP into biodegradable nanoparticles (NPs) using poly (dl-lactic-co-glycolic acid) (PLGA). The impacts of various formulation variables on the physicochemical characteristics of the ZP-PLGA-NPs and drug release profiles were investigated. Pharmacokinetics and pharmacological activity of ZP-PLGA-NPs were studied using experimental animals and were compared with generic ZP tablets. Assessment of gamma-aminobutyric acid (GABA) level in plasma after oral administration was conducted using enzyme-linked immunosorbent assay. The maximal electroshock-induced seizures model evaluated anticonvulsant activity after the parenteral administration of ZP-loaded NPs. The prepared ZP-PLGA NPs were negatively charged spherical particles with an average size of 120-300 nm. Optimized ZP-PLGA NPs showed higher plasma GABA levels, longer sedative, hypnotic effects, and a 3.42-fold augmentation in oral drug bioavailability in comparison to ZP-marketed products. Moreover, parenteral administration of ZP-NPs showed higher anticonvulsant activity compared to free drug. Oral administration of ZP-PLGA NPs achieved a significant improvement in the drug bioavailability, and parenteral administration showed a pronounced anticonvulsant activity.

The Z-Drugs Zolpidem, Zaleplon, and Eszopiclone Have Varying Actions on Human GABA A Receptors Containing γ1, γ2, and γ3 Subunits.

γ-Aminobutyric-acid type A (GABA A ) receptors expressing the γ1 or γ3 subunit are only found within a few regions of the brain, some of which are involved in sleep. No known compounds have been reported to selectively target γ1- or γ3-containing GABA A receptors. Pharmacological assessments of this are conflicting, possibly due to differences in experimental models, conditions, and exact protocols when reporting efficacies and potencies. In this study, we evaluated the modulatory properties of five non-benzodiazepine Z-drugs (zaleplon, indiplon, eszopiclone, zolpidem, and alpidem) used in sleep management and the benzodiazepine, diazepam on human α1ß2γ receptors using all three γ subtypes. This was accomplished using concatenated GABA A pentamers expressed in Xenopus laevis oocytes and measured via two-electrode voltage clamp. This approach removes the potential for single subunits to form erroneous receptors that could contribute to the pharmacological assessment of these compounds. No compound tested had significant effects on γ1-containing receptors below 10 µM. Interestingly, zaleplon and indiplon were found to modulate γ3-containing receptors equally as efficacious as γ2-containing receptors. Furthermore, zaleplon had a higher potency for γ3- than for γ2-containing receptors, indicating certain therapeutic effects could occur via these γ3-containing receptors. Eszopiclone modulated γ3-containing receptors with reduced efficacy but no reduction in potency. These data demonstrate that the imidazopyridines zaleplon and indiplon are well suited to further investigate potential γ3 effects on sleep in vivo.

Association of eszopiclone, zaleplon, or zolpidem with complex sleep behaviors resulting in serious injuries, including death.

PURPOSE: To identify and analyze postmarketing cases of complex sleep behaviors (CSBs) resulting in serious injuries, including death, associated with eszopiclone, zaleplon, or zolpidem (Z-drugs). METHODS: Retrospective analysis of the U.S. Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS) from 16 December 1992 through 27 February 2018 and medical literature using PubMed and EMBASE. We used random sampling and descriptive statistics. RESULTS: We identified 66 cases that met inclusion and exclusion criteria, four of which were identified in the medical literature. Twenty cases reported death and 46 cases reported serious injuries in association with CSBs occurring after the use of a Z-drug. Fatal cases described events, such as carbon monoxide poisoning, drowning, falls, hypothermia, motor vehicle collisions, and apparent completed suicide. Nonfatal cases resulting in serious injuries described events, such as accidental overdoses, falls, gunshot wounds, hypothermia, third-degree burns, and self-injuries or suicide attempts. Twenty-two cases reported a previous episode of a CSB while taking a Z-drug prior to the event reported in this case series. CONCLUSIONS: The FAERS and medical literature cases support the need for increased awareness of the consequences that may occur because of CSBs associated with the use of Z-drugs. Therefore, to protect public health, regulatory actions were taken, including adding a Boxed Warning, a Contraindication in patients who have experienced a prior episode of a CSB with a Z-drug, and updating the existing Warnings and Precautions. An FDA Drug Safety Communication was also disseminated to alert healthcare professionals and the public of this potential risk.

Enhancement of zaleplon oral bioavailability using optimized self-nano emulsifying drug delivery systems and its effect on sleep quality among a sample of psychiatric patients.

The aim of this work is to develop self-nano emulsifying drug delivery system (SNEDDS) to enhance the oral bioavailability of zaleplon (Zal) as a poorly water-soluble drug. Moreover, the bioavailability and the effect on the quality of sleep among a sample of psychiatric patients is to be assessed. D-optimal mixture design was used for optimization. Optimized SNEDDS formulation was evaluated for droplet size, transmission electron microscope (TEM) and in-vitro dissolution test. Zal bioavailability was evaluated by determining its serum concentration and pharmacokinetic parameters in 8 patients after oral administration. Effect on sleep quality was assessed among 40 psychiatric patients. Patients' sleep quality was assessed in 40 psychiatric patients before and after medication using the Arabic version of the Pittsburgh Sleep Quality Index (PSQI). Zal- SNEDDS appeared as nano-sized spherical vesicles. Moreover, Zal was completely dissolved from optimized formulation after 45 min indicating improved dissolution rate. Zal-SNEDDS showed significantly higher Cmax, Tmax and AUC0→∞ compared to commercial product after oral administration. Zal-SNEDDS significantly improved the total score of PSQIs (p < .001) with higher subjective sleep quality, reduced sleep latency, improved day time function and sleep disturbance (p < .001). Using sleep medication was reduced significantly (p = .027). However, it did not modify sleep duration or sleep efficiency. SNEDDS have improved Zal solubility and enhanced its bioavailability. Furthermore, Zal-SNEDDS have improved the total score of PSQIs and may be considered a good choice to enhance the quality of sleep among psychiatric patients.

An Insight into Z-Drug Abuse and Dependence: An Examination of Reports to the European Medicines Agency Database of Suspected Adverse Drug Reactions.

BACKGROUND: Although originally marketed as safe alternatives to the habit-forming benzodiazepines, growing numbers of zaleplon, zolpidem, and zopiclone ("Z-drugs") clinical concerns relating to their potential of abuse, dependence, and withdrawal have been reported over time. We aimed here at assessing these issues analyzing datasets of adverse drug reactions provided by the European Medicines Agency through the EudraVigilance system. METHODS: Analyzing the adverse drug reactions databases of each Z-drug, descriptive analyses have been performed on cases and proportional reporting ratios (PRRs) computed. RESULTS: An overall number of 33 240 (e.g., 23 420 zolpidem; 9283 zopiclone; and 537 zaleplon) misuse-, abuse-, dependence-, and withdrawal-related adverse drug reactions, corresponding to some 6246 unique patients given Z-drugs, were here identified. Cases were studied and described, including demographic characteristics and clinical data such as concomitant drugs, doses, routes of administration, and outcomes of the reactions (being fatalities recorded). Considering PRR values and in comparison with zopiclone, zolpidem was more frequently involved in both misuse/abuse and withdrawal issues. Zolpidem and zopiclone presented with the same dependence risk, but zopiclone was most involved in overdose adverse drug reactions. Compared with zaleplon, zopiclone presented higher dependence and overdose-related issues but slightly lower misuse/abuse and withdrawal PRR values. CONCLUSION: Current data may only represent a gross underestimate of the real prevalence of Z-drug misuse. Caution should be exercised when prescribing those molecules, especially for patients with psychiatric illnesses and/or history of drug abuse. We recommend the need to invest in proactive pharmacovigilance activities to better and promptly detect, understand, and prevent any possible misuse potential of prescribed medications.

Solvent effects on the absorption and fluorescence spectra of Zaleplon: Determination of ground and excited state dipole moments.

Solvent effects on the absorption and fluorescence spectra of Zaleplon, a nonbenzodiazepine sedative/hypnotic drug that is mainly used for the short term treatment of insomnia, were investigated in 18 different solvents with diverse polarities. Dipole moments of the ground and excited state (µg and µe) were determined by Lippert-Mataga, Bakhshiev, Reichardt, McRae and Suppan solvatochromic methods. The dipole moment of Zaleplon ground state in the gas phase has been calculated as µg = 10.95 D (TD-DFT) with B3LYP/cc-pVTZ functional. There is a good agreement of theoretical data with Reichardt, McRae, and Suppan correlations, while some dissidence with Lippert-Mataga and Bakhshiev equations is suggesting the occurrence of specific solute-solvent interactions. Additionally, multiple linear regression analysis with Kamlet-Taft and Catalan solvatochromic models was applied to solute-solvent interactions. Dominant property of the solvent that affects the absorption band and Stokes shifts of Zaleplon is polarity of the solvent while the emission band is influenced mainly by solvent basicity.

Zaleplon loaded bi-layered chronopatch: A novel buccal chronodelivery approach to overcome circadian rhythm related sleep disorder.

The aim of this study was to develop a novel buccal bi-layered chronopatch capable of eliciting pulsatile release pattern of drugs treating diseases with circadian rhythm related manifestation. Zaleplon (ZLP) was used as a model drug intended to induce sleep and to treat middle of night insomnia. The chronopatch was prepared adopting double casting technique. The first layer was composed of a controlled release patch containing ZLP-Precirol melt granules intended to release ZLP in a sustained manner to maintain sleep and to prevent early morning awakening. The second layer was composed of a fast release lyophilized buccal disc containing ZLP loaded SNEDDS (Z-SNEDDS) intended for rapid sleep induction. Pharmacokinetic parameters of ZLP from the chronopatch were compared to those of the immediate release capsule, Siesta®, as reference in Mongrel dogs using a randomized crossover design. The appearance of two peaks having two Cmax and Tmax proved the pulsatile release pattern. The increase in relative bioavailability of ZLP from the chronopatch was 2.63 folds. The results revealed the ability of the developed ZLP loaded bi-layered chronopatch to be a candidate for overcoming early morning awakening without middle of night dose administration.

Initiation and long-term use of benzodiazepines and Z-drugs in bipolar disorder.

OBJECTIVES: Increasing evidence points to the harmful effects of long-term benzodiazepine treatment. Our objective was to study the incidence of, and predictors for, long-term use of benzodiazepines and Z-drugs in bipolar disorder. METHODS: We conducted a population-based cohort study, using data from Swedish national registers. Swedish residents aged 18-75 years with a recorded diagnosis of bipolar disorder or mania between July 2006 and December 2012, and no history of benzodiazepine/Z-drug use in the past year, were included. Patients were followed for 1 year with regard to prescription fills of benzodiazepines/Z-drugs. Initiators were followed for another year during which continuous use for >6 months was defined as "long-term". Patient and prescription characteristics were investigated as potential predictors for long-term use in multivariate logistic regression models. RESULTS: Out of the 21 883 patients included, 29% started benzodiazepine/Z-drug treatment, of whom one in five became long-term users. Patients who were prescribed clonazepam or alprazolam had high odds for subsequent long-term use (adjusted odds ratios [aORs] 3.78 [95% confidence interval (CI) 2.24-6.38] and 2.03 [95% CI 1.30-3.18], respectively), compared to those prescribed diazepam. Polytherapy with benzodiazepines/Z-drugs also predicted long-term use (aOR 2.46, 95% CI 1.79-3.38), as did age ≥60 years (aOR 1.93, 95% CI 1.46-2.53, compared to age <30 years), and concomitant treatment with psychostimulants (aOR 1.78, 95% CI 1.33-2.39). CONCLUSIONS: The incidence of subsequent long-term use among bipolar benzodiazepine initiators is high. Patients on clonazepam, alprazolam or benzodiazepine/Z-drug polytherapy have the highest risk of becoming long-term users, suggesting that these treatments should be used restrictively.