Single Dose Of Diazepam Research Articles

Ceftriaxone Inhibits Conditioned Fear and Compulsive-like Repetitive Marble Digging without Central Nervous System Side Effects Typical of Diazepam-A Study on DBA2/J Mice and a High-5HT Subline of Wistar-Zagreb 5HT Rats.

Background: Ceftriaxone upregulates GLT1 glutamate transporter in the brain and may have anti-CFC and anti-OCD effects. Methods: Twenty WZ-5HT rats were used to investigate the effects of ceftriaxone on obsessive-compulsive (OCD)-like behaviour in the marble-burying (MB) test, freezing behaviour in contextual fear conditioning (CFC) and expression of GLT1 protein in the hippocampus or amygdala using immunoblots. Fifteen DBA/2J mice were used in the MB test. We also compared diazepam with ceftriaxone in open-field, beam-walking, and wire-hanging tests on 47 DBA/2J mice. Ceftriaxone (200 mg/kg) and saline were applied intraperitoneally, once daily for 7 (rats) or 5 (mice) consecutive days. A single dose of diazepam (1.5-3.0 mg/kg) or saline was injected 30 min before the behavioural tests. Results: Ceftriaxone significantly diminished OCD-like behaviour (↓ number of marbles buried) and freezing behaviour in CFC context session (↑ latencies, ↓ total duration, ↓ duration over four 2 min periods of the session) but increased GLT1 protein expression in the amygdala and hippocampus of rats. Diazepam induced sedation, ataxia and myorelaxation in mice. Ceftriaxone did not have these side effects. Conclusions: The results of this study confirm the anti-CFC and anti-OCD effects of ceftriaxone, which did not produce the unwanted effects typical of diazepam.

Therapeutic Dose of Metoclopramide Induced Dystonic Reacton in Children

Metoclopramide is a dopamine antagonist that is used in gastro esophageal disease and enteritis in adults and pediatric. The major side effects are extrapyramidal symptoms. They appear as dystonic movements. These are more common in children and young adults, especially in females. This retrospective descriptive study was conducted in Misurata Medical Center. It is aimed to draw attention to the frequent occurrence of metoclopramide-induced side-reactions. We studied the files of 45 patients who had been exposed to this reaction between the years of 2006 to 2008. Different dosage form of metoclopramide found to induced this acute reaction. Dystonia was occurred in 18 (40%) children who received drops, 10 (22%) patients received injection, and 6 (13.33%) children received syrup, while one patient received a tablet. The other children had received two dosage forms as injection with drops, syrup or suppository. All 45 children were treated intravenously with a single dose of diazepam. Young children especially females are more susceptible to dystonic reactions form metoclopramide. Our study indicates that diazepam is effective drug to abolish this adverse reaction.

Deposition of diazepam and its metabolites in hair following a single dose of diazepam.

Only sporadic data are available on hair concentrations of diazepam and some of its metabolites (nordazepam, oxazepam, and temazepam) following a single controlled dose. The aim of this study was to investigate the deposition of diazepam and its metabolites in human hair after eight healthy volunteers (four women and four men, ages 24-26, East Asian) consumed 10mg of diazepam. Hair was collected from all volunteers 1month after exposure, and also 2months post-exposure from men and 10months post-exposure from women. Diazepam and the complete metabolite profile, including oxazepam glucuronide and temazepam glucuronide, were measured by ultra-high pressure liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) with limits of quantifications (LOQs) of 0.5-2.5pg/mg for diazepam, nordazepam, oxazepam, and temazepam, and of 10pg/mg for oxazepam glucuronide and temazepam glucuronide. There were no differences by gender in the amounts of diazepam or metabolites found. The concentration of the main metabolite nordazepam was consistently higher than that of diazepam at both 1 and 2months after consumption. Oxazepam and temazepam traces were found in some volunteers' hair, but the glucuronides were not detected. Diazepam and nordazepam levels at 10months post-exposure were extremely low (near the LOQ), indicating drug loss by personal hygiene and physical handling. To our knowledge, this is the first single-dose diazepam study using black hair and the first study to include measurements of oxazepam glucuronide and temazepam glucuronide in human hair.

Prefrontal activity decline in women under a single dose of diazepam during rule-guided responses: an fMRI study.

Daily life events confront us with new situations demanding responses to usual and unusual rules. Diazepam (DZ), a clinically important drug, facilitates the inhibitory activity of the GABAergic system. Prefrontal cortex, rich in DZ receptors, coordinates necessary resources to direct actions according to rules. The balance between excitatory and inhibitory activity is critical to achieve optimal function of brain systems leading to complex functions. Major sex differences in the physiological mechanisms of the GABAergic system have been reported. However, the differential influence of DZ on men and women in neural activity during behavior directed by frontal lobes remains unexplored. The ability of healthy volunteers to select responses following usual/congruent and novel/incongruent rules, and brain correlates were measured with fMRI under the administration of DZ and a placebo. 10mg of DZ was enough to decrease the performance in a different manner between men and women. While reaction times increased in both men and women, women committed more errors selecting responses than men under DZ. Men demonstrated increased activity, while women demonstrated decreased activity in frontal regions involved in response selection of rules. These findings could have important consequences in understanding the differential influences of DZ between the sexes in complex daily life situations. More importantly, this study emphasizes the importance of understanding the differential effects on men and women of drugs widely employed by society, thereby achieves better therapeutic results and avoids side effects that the present study revealed to be different between sexes.

Inhibition of Neuropathic Pain by a Single Intraperitoneal Injection of Diazepam in the Rat: Possible Role of Neurosteroids.

Diazepam binds with the same high affinity to the central benzodiazepine receptor (CBR) and the peripheral benzodiazepine receptor, which has been renamed translocator protein (TSPO). Both receptors could promote neurosteroid synthesis. In the present study, we investigated whether a single dose of diazepam could inhibit neuropathic pain induced by L5 spinal nerve ligation (L5 SNL), and whether CBR and TSPO mediated this effect. We found that a single intraperitoneal injection of diazepam 9 d after L5 SNL significantly depressed the established mechanical allodynia and thermal hyperalgesia, which persisted until the end of the experiments. Furthermore, the effects were mimicked by a single intraperitoneal injection of Ro5-4864, a specific TSPO agonist and pregnenolone, a neurosteroid precursor. In addition, we found that the inhibitory effect of diazepam was also completely blocked by pretreatment with a specific CBR antagonist, flumazenil. The effects of diazepam or Ro5-4864 on neuropathic pain were completely blocked by pretreatment with a neurosteroid synthesis inhibitor, aminoglutethimide (AMG). Finally, any one of the three drugs, diazepam, Ro5-4864 and pregnenolone, could reduce the activation of astrocytes and the production of interleukin-1beta (IL-1β) in the L5 spinal dorsal horn 14 d after L5 SNL. These results suggest that in addition to exerting effects on CBR, diazepam may inhibit neuropathic pain via TSPO, which promotes neurosteroid formation, subsequently reducing the activation of astrocytes and production of cytokines.

Diazepam leads to enhanced severity of orthopoxvirus infection and immune suppression

Benzodiazepines are drugs widely used as tranquilizers and in various other indications. We treated Balb/c mice with diazepam and infected them with cowpox (CPXV) and vaccinia virus (VACV). Disease index, weight loss and the antibody response were determined. Additionally the influence of different benzodiazepines on the mitogen response of human peripheral blood lymphocytes and spleen cells was tested. Diazepam led to earlier disease onset, prolonged duration of symptoms, higher weight loss and overall disease index in VACV infected mice. CPXV infected mice developed poxviral skin lesions only after drug administration and a significant decrease in the specific antibody response was also observed. Diazepam and alprazolam also inhibited the proliferative response of human lymphocytes/spleen cells in vitro but did not show noteworthy apoptotic effects. It is surprising that even a single dose of diazepam has a profound influence on the immune system, sufficient to facilitate symptomatic infectious disease. These data provide first evidence that commonly used drugs like Valium ® may augment severity of rare poxvirus infections such as CPXV or monkeypox. As VACV is still used as life vaccine against smallpox there is also a risk of enhanced side effects or possible interference with the success of vaccination.

Diazepam-induced adaptive plasticity revealed by alpha1 GABAA receptor-specific expression profiling.

Benzodiazepines are in wide clinical use for their sedative and tranquilizing actions, the former being mediated via alpha1-containing GABAA receptors. The signal transduction pathways elicited beyond the receptor are only poorly understood. Changes of transcript levels in cerebral cortex induced by acute diazepam administration were therefore compared by microarray analysis between wild-type and point mutated alpha1(H101R) mice, in which the alpha1 GABAA receptor subunit had been rendered insensitive to diazepam. In wild-type animals, diazepam reduced the expression levels of the alpha subunit of the calcium/calmodulin-dependent protein kinase II, as well as brain-derived neurotrophic factor, MAP kinase phosphatase, transcription factor GIF, c-fos and nerve growth factor induced gene-A. None of these transcripts was changed in the alpha1(H101R) mice after treatment with diazepam. Thus, the sedative action of diazepam is correlated with a selective down-regulation of transcripts involved in the regulation of neuronal plasticity and neurotrophic responses. Most transcript changes were transient except for the decrease of the CaMKIIalpha transcript which persisted even 40 h after the single dose of diazepam. This long-term alteration is likely to contribute to the resetting of the neuronal responsiveness, which may be involved in rebound phenomena and, under chronic treatment, in the development of tolerance and dependence.

An anxiolytic-like effect of Ginkgo biloba extract and its constituent, ginkgolide-A, in mice.

The anxiolytic-like effects of Ginkgo biloba extract (GBE) and its four terpenoid components (ginkgolide-A, ginkgolide-B, ginkgolide-C, and bilobalide) were assessed using the elevated plus-maze test in mice. Administration of GBE as a single oral dose (0.5 or 1 g/kg, po) caused a state of suppressed motor activity and, thus, shortened the time spent in the open-sided arms. However, when GBE (0.063-1 g/kg, po) was administered daily for 7 days and the plus-maze test was carried out 24 h after the final administration, the time spent in the open-sided arms was prolonged, with the peak anxiolytic-like effect at 0.125 g/kg. A combination of seven-day administration of GBE (0.125 g/kg) and a single dose of diazepam (1 mg/ kg, po, 10 min before testing) enhanced the anxiolytic-like effect. Flumazenil (0.3 mg/kg, ip, 10 min before testing) blocked the effect of diazepam, but not of GBE. Daily administration of ginkgolide-A (1 or 2 mg/kg, po) resulted in an anxiolytic-like effect by the third treatment, with the maximal effect observed after the fifth administration. Neither ginkgolide-B, ginkgolide-C, nor bilobalide produced any anxiolytic-like effects. At doses higher than 0.5 g/kg, GBE not only inhibited motor activity but also suppressed active avoidance behavior, reduced caffeine-induced stimulation, and enhanced pentobarbital-induced sleep, while ginkgolide-A (up to 20 mg/kg) did not exhibit these effects. Diazepam (1 mg/kg) is known to enhance pentobarbital-induced sleep. These results suggest that GBE produces a significant anxiolytic-like effect following repeated administration and that ginkgolide-A is most likely responsible for this effect. There are also indications that although GBE exerts a sedative effect at comparatively higher doses, ginkgolide-A has a relatively weak tendency to produce benzodiazepine-like side effects.

AIT-082 Is Neuroprotective against Kainate-Induced Neuronal Injury in Rats

4-[[3-(1,6-dihydro-6-oxo-9-purin-9-yl)-1-oxopropyl]amino]benzoic acid (AIT-082) is an hypoxanthine derivative that stimulates in vitro neurite outgrowth and the production of adenosine and neurotrophins from astrocytes. These effects may predict an in vivo neuroprotective activity of the drug. Thus, we evaluated whether AIT-082 protected against a long-term excitotoxicity of hippocampal neurons following status epilepticus induced in rats by i.p. injection of kainate (12 mg/kg). The epileptogenic effect of kainate was evaluated by monitoring behavioral signs and by electroencephalographic (EEG) recording (80% of the animals showed status epilepticus with a latency of 96.8 ± 7.4 min starting from the injection). In surviving rats (40% of the injected animals) the neurotoxic effect was evaluated by measuring glutamic acid decarboxylase (GAD) activity, as an index of loss of hippocampal GABAergic neurons, by evaluating the body weight after 7 days and by histological examination of hippocampi. The GAD activity was reduced by 44 ± 8%, and neuronal loss (about 70%) was found in the CA3c, the CA1 area, and in the dentate gyrus. A single dose of diazepam (20 mg/kg; i.p., 20 min before the kainate injection) almost completely inhibited both seizures and neurotoxicity, ensuring survival of animals. AIT-082 (60 mg/kg/day; i.p., for 7 days, starting from 20 min before the kainate injection) did not modify the seizures caused by kainate but, like diazepam, it decreased kainate-induced mortality, the reduction of GAD activity, and the loss of hippocampal neurons. These data confirm that AIT-082 is of potential interest for the experimental therapy of neurodegenerative disorders.

Decreased GABA enhancement of benzodiazepine binding after a single dose of diazepam.

The GABA and benzodiazepine binding sites on GABA(A) receptors are allosterically coupled. The in vitro binding of 2 nM [3H]flunitrazepam to cortical and cerebellar membranes prepared from drug-naive rats was potentiated approximately 1.6-fold by 100 microM GABA. Potentiation in both regions was significantly reduced 4 or 12 but not 24 h after a single dose of 15 mg/kg diazepam. At 24 h after the last of 14 daily doses of diazepam, no differences in GABA potentiation were observed. Diazepam-induced changes in GABA(A) receptor gamma2-subunit gene transcription and alpha1-, beta2-, and gamma2-subunit steady-state mRNA levels did not appear to be temporally related to allosteric uncoupling.

Children presenting with convulsions (including status epilepticus) to a paediatric accident and emergency department: an audit of a treatment protocol.

All children who presented in a convulsion, including convulsive status epilepticus, to the accident and emergency department over a 12-month period and who required treatment, were reviewed retrospectively to identify the effectiveness and safety of a specific treatment protocol. This protocol recommends the initial use of one, or if necessary, two doses of rectal or intravenous diazepam (0.4 mg/kg) followed by the simultaneous administration of phenytoin (18 mg/kg) and rectal paraldehyde (0.4 mL/kg), with instructions for maximum doses and timings of administration. Eighty-one evaluable children (52 male) were audited. The mean age of the study population was 4.1 (range 0.1 to 14.9) years. Overall, the presenting convulsion was successfully terminated in 76 children (94%) within the accident and emergency department. In 69 children (85% of the entire study population) this was after a single dose of diazepam (rectal in 41 and intravenous in 28). In only an additional two children did the presenting convulsion stop after a second dose of diazepam. In five of the 10 children (50%) who received paraldehyde and phenytoin as a combination, the convulsion stopped. Nine patients (11%) required admission to the intensive-care unit, five because of persisting convulsive activity, and four because of respiratory depression. The results of this retrospective audit suggest that the current treatment protocol appears to be effective and relatively safe in treating acute convulsions, including convulsive status epilepticus. The audit is to be repeated prospectively to either confirm or refute these findings before recommending any changes to the protocol.

Children presenting with convulsions (including status epilepticus) to a paediatric accident and emergency department: an audit of a treatment protocol

All children who presented in a convulsion, including convulsive status epilepticus, to the accident and emergency department over a 12‐month period and who required treatment, were reviewed retrospectively to identify the effectiveness and safety of a specific treatment protocol. This protocol recommends the initial use of one, or if necessary, two doses of rectal or intravenous diazepam (0.4 mg/kg) followed by the simultaneous administration of phenytoin (18 mg/kg) and rectal paraldehyde (0.4 mL/kg), with instructions for maximum doses and timings of administration. Eighty‐one evaluable children (52 male) were audited. The mean age of the study population was 4.1 (range 0.1 to 14.9) years. Overall, the presenting convulsion was successfully terminated in 76 children (94%) within the accident and emergency department. In 69 children (85% of the entire study population) this was after a single dose of diazepam (rectal in 41 and intravenous in 28). In only an additional two children did the presenting convulsion stop after a second dose of diazepam. In five of the 10 children (50%) who received paraldehyde and phenytoin as a combination, the convulsion stopped. Nine patients (11%) required admission to the intensive‐care unit, five because of persisting convulsive activity, and four because of respiratory depression. The results of this retrospective audit suggest that the current treatment protocol appears to be effective and relatively safe in treating acute convulsions, including convulsive status epilepticus. The audit is to be repeated prospectively to either confirm or refute these findings before recommending any changes to the protocol.

Diazepam induced early oxidative changes at the subcellular level in rat brain.

Studies were conducted to ascertain any involvement of free radical mediated prooxidative processes in different brain regions following diazepam administration. A significant decrease in TBA reactive substance formation was observed in cerebral cortex, cerebellum and brain stem regions after single doses of 1.5, 3 and 6 mg/kg b.wt. For further studies rats were given diazepam (i.p.) at 3 mg/kg body weight dose and sacrificed after 1 h to follow changes in the pro/antioxidant status. An enhancement in the TBARS formation was found in the mitochondrial fractions from cerebral cortex and brain stem. This effect was highest in brain stem being 107% as compared to controls. In the post mitochondrial fraction, cerebellum showed 49% enhancement whereas decreased formation of thiobarbituric acid reactive substances was observed in cerebral cortex and brain stem. Isozymes of superoxide dismutase showed a decrease in activity which was region dependent. Even though, total thiols were not significantly altered, free thiols showed depletion in cerebellum (39.8%) and brain stem (50%). Glutathione reductase activity was also decreased in cerebellum and brain stem. The results indicate that a single dose of diazepam causes free radical mediated changes and the modulatory response of antioxidant defences appears to be region specific.

Rapid tolerance to benzodiazepine modifies rat hippocampal synaptic plasticity

Glutamate antagonists to N-methyl- d-aspartate (NMDA) receptors blocks the development of ‘rapid’ tolerance to the sedative action of benzodiazepines (BZDs). This kind of glutamate receptors is closely related to synaptic plasticity in different areas of the brain such as hippocampus. In the present investigation, we studied the synaptic plasticity in dentate gyrus of the hippocampus during the development of tolerance to the hypomotility action induced by diazepam (DZ). The results show an increased hippocampal synaptic plasticity in slices from rats treated with diazepam (5 mg/kg per day) during 4 days, assessed as a decrease of the threshold in the stimulation frequency for long-term potentiation (LTP) elicitation. Thus, a single dose of DZ does not change the ease of induction of LTP but does change locomotor behavior; multiple DZ doses change LTP but not locomotor behavior. Our results reveal a positive correlation between the synaptic plasticity and development of BZD tolerance to locomotor activity.

The digit vigilance test: reliability, validity, and sensitivity to diazepam

The Digit Vigilance Test (DVT), a measure of sustained attention and psychomotor speed, was evaluated in terms of test-retest and alternate-form reliability as well as sensitivity to a single dose of diazepam (10 mg). A one-page version was compared to the standard two-page format. Forty undergraduates, randomly assigned in a double-blind manner to either drug or placebo condition, were tested three times in two sessions (1 week apart). Both Page 1 and Total Time scores were found to be highly reliable across time and forms. Repeated measures ANOVAs revealed the Total Time score, but not the Page 1 score, to be significant in discriminating diazepam from placebo across time, supporting the use of the complete DVT for measuring drug effects. Findings based on convergent measures also help to validate the DVT as a measure of sustained attention.

Common genetic determinants of severity of acute withdrawal from ethanol, pentobarbital and diazepam in inbred mice.

Severity of drug withdrawal is in part genetically mediated, and can be indexed by exacerbation of the handling-induced convulsion in mice. Acute withdrawal has been reported following single injections of hypnotic doses of ethanol and pento-barbital, and can be precipitated by injection of flumazenil following a single dose of diazepam. Results with Swiss-Webster mice indicate that the magnitude of ethanol and diazepam withdrawal severity did not differ across a range of doses in the acute paradigm. We characterized 15 inbred mouse strains for handling-induced convulsion severity following administration of standard doses of each of these drugs. Significant strain differences in withdrawal severity were found for each drug. Two of the strains showed a tendency toward more pronounced withdrawal from all drugs, while six strains showed low withdrawal from all drugs. The correlations among strain mean withdrawal responses were analyzed to estimate common genetic influences. Ethanol and pentobarbital withdrawal severities were positively genetically correlated, indicating influence of some genes on both responses. A positive genetic correlation was also found between the severity of the withdrawal from pentobarbital and diazepam; however, diazepam and ethanol withdrawal severities were not found to be genetically related. These experiments suggest that some genes influence severity of withdrawal from more than one subclass of depressant drugs.

The effect of intravenously administered diazepam, midazolam and flumazenil on the sensitivity of upper airway reflexes

This investigation studied the effect of two intravenous benzodiazepines and the specific reversal agent, flumazenil, on the sensitivity of upper airway reflexes. In a blinded, randomised, crossover study, we have investigated the effect of a single dose of diazepam ('Diazemuls') (0.2 mg.kg-1) and midazolam (0.07 mg.kg-1), both given intravenously on the sensitivity of upper airway reflexes in eight male volunteers. Reflex sensitivity was assessed by identification of reflex glottic closure in response to a threshold concentration of inhaled ammonia vapour. Both diazepam and midazolam produced significant depression of upper airway reflex sensitivity. This was maximum with both drugs within 10 min of administration, but baseline sensitivity was regained within 60 min. Flumazenil (300 micrograms) administered 10 min after midazolam, resulted in significant reversal of the upper airway reflex sensitivity depression.

Influence of Diazepam on the Pharmacokinetic Properties of Orally Administered Naproxen

The effect of a single dose of diazepam on the pharmacokinetics of naproxen was studied in 10 healthy subjects by administering in a crossover design single doses of naproxen 500mg alone or in combination with 10mg of diazepam. Mean peak serum naproxen concentrations were lowered (83.4 to 64.5 mg/L), the time to peak concentration was increased (1.36 to 2.0h) and the absorption rate was decreased (4.07 to 2.42h−1) when naproxen was administered with diazepam. However, none of the other pharmacokinetic parameters of the drug were significantly altered in the presence of diazepam.

Muscimol-associated changes in local cerebral glucose use following chronic diazepam administration

Local cerebral glucose use (LCGU) was determined in parallel groups of conscious rats receiving muscimol (1.5 mg/kg i.v.) after either saline pretreatment (28 days i.p.), saline pretreatment (27 days i.p.) followed by a single dose of diazepam (5 mg/kg i.p.) 24 h prior to muscimol administration, or chronic diazepam pretreatment (5 mg/kg i.p. daily for 28 days). Acute administration of muscimol produced a significant reduction in LCGU in 25 out of 66 structures examined compared with vehicle-treated controls. The pattern of reductions was heterogeneous. Thalamic and most cortical areas showed reductions of the order of 30–45%, whereas more modest depressions of 15–20% were observed in some limbic structures (e.g. basolateral amygdala, anterior thalamic nuclei, nucleus accumbens, subiculum). This contrasts with the more extensive and homogeneous pattern of LGCU reductions (around 20%) produced by diazepam. Neither acute diazepam treatment the previous day nor chronic diazepam pretreatment altered the LGCU response to muscimol. These data suggest that high-affinity GABA receptor-mediated responses are unchanged by both acute and chronic benzodiazepine pretreatment. It would appear unlikely that alterations in these responses contribute to the mechanism of benzodiazepine tolerance.

Effect of omeprazole and cimetidine on plasma diazepam levels

The effects of steady state dosing with omeprazole and cimetidine on plasma diazepam levels have been studied in 12 healthy males. Single doses of diazepam (0.1 mg.kg-1 i.v.) were administered after one week of treatment with omeprazole 20 mg once daily, cimetidine 400 mg b.d. or placebo, and the treatment was continued for a further 5 days. Blood was collected for 120 h after the dose of diazepam for the measurement of diazepam and its major metabolite desmethyl diazepam. The mean clearance of diazepam was decreased by 27% and 38% and its half-life was increased by 36% and 39% after omeprazole and cimetidine, respectively. Neither drug had any apparent effect on the volume of distribution of diazepam. Desmethyldiazepam appeared more slowly after both omeprazole and cimetidine. It is concluded that the decrease in diazepam clearance was associated with inhibition of hepatic metabolism both by omeprazole and cimetidine. However, since diazepam has a wide therapeutic range, it is unlikely that concomitant treatment with therapeutically recommended doses of either omeprazole or cimetidine will result in a clinically significant interaction with diazepam.