Metabolic profile of oxazepam and related benzodiazepines: clinical and forensic aspects.

Anxiolytic drugs, namely benzodiazepines, are the most commonly used psychoactive substances since anxiety disorders are prevalent mental disorders particularly in the Western world. Oxazepam is a short-acting benzodiazepine and one of the most frequently prescribed anxiolytic drugs. It is also the active metabolite of a wide range of other benzodiazepines, such as diazepam, ketazolam, temazepam, chlordiazepoxide, demoxazepam, halazepam, medazepam, prazepam, pinazepam, and chlorazepate. Therefore, relevant clinical and forensic outocomes may arise, namely those related to interference in driving performance. It is clinically available as a racemic formulation, with S-enantiomer being more active than R-enantiomer. In humans, it is mainly polimorphically metabolized by glucuronide conjugation at the 3-carbon hydroxyl group, yielding stable diastereomeric glucuronides (R- and S-oxazepam glucuronide). Relevant metabolic and stereoselective interspecies differences have been reported. In this work, the pharmacokinetics of oxazepam with particular focus on metabolic pathways is fully reviewed. Moreover, the metabolic profile of other prescribed benzodiazepines that produce oxazepam as a metabolite is also discussed. It is aimed that knowing the metabolism of oxazepam and related benzodiazepines may lead to the development of new analytical strategies for its early detection and help in further toxicological and clinical interpretations.

Assessing prescription drug abuse using functional principal component analysis (FPCA) of wastewater data.

BACKGROUND: Wastewater-based epidemiology is an alternative method for estimating the collective drug use in a community. We applied functional data analysis, a statistical framework developed for analysing curve data, to investigate weekly temporal patterns in wastewater measurements of three prescription drugs with known abuse potential: methadone, oxazepam and methylphenidate, comparing them to positive and negative control drugs. METHODS: Sewage samples were collected in February 2014 from a wastewater treatment plant in Oslo, Norway. The weekly pattern of each drug was extracted by fitting of generalized additive models, using trigonometric functions to model the cyclic behaviour. From the weekly component, the main temporal features were then extracted using functional principal component analysis. Results are presented through the functional principal components (FPCs) and corresponding FPC scores. RESULTS: Clinically, the most important weekly feature of the wastewater-based epidemiology data was the second FPC, representing the difference between average midweek level and a peak during the weekend, representing possible recreational use of a drug in the weekend. Estimated scores on this FPC indicated recreational use of methylphenidate, with a high weekend peak, but not for methadone and oxazepam. CONCLUSION: The functional principal component analysis uncovered clinically important temporal features of the weekly patterns of the use of prescription drugs detected from wastewater analysis. This may be used as a post-marketing surveillance method to monitor prescription drugs with abuse potential. Copyright © 2016 John Wiley & Sons, Ltd.

Population Pharmacokinetics of High-Dose Oxazepam in Alcohol-Dependent Patients: Is There a Risk of Accumulation?

BACKGROUND: According to the guidelines, benzodiazepines with a short half-life are the reference medication to treat alcohol withdrawal syndrome. The doses of oxazepam used in this population may reach up to 300 mg per day, significantly higher than usual doses. Its use in these patients deserves further information to confirm that the half-life remains constant and that no accumulation appears. The objective of this study was to investigate the pharmacokinetics of high doses of oxazepam in alcohol-dependent patients treated for alcohol withdrawal syndrome. METHODS: Overall, 63 outpatients [weight, 71.1 kg (45.0-118.0); age, 47.6 years (31-67)] followed in the addictology unit, were studied. Total mean dose of 96.0 mg per day (range, 20-300 mg/d) was administered by oral route. Therapeutic drug monitoring allowed the measurement of 96 plasma concentrations. The following covariates were evaluated: demographic data (age, body weight, height, gender) and biological data (creatinine, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, gamma-glutamyl transferase). Pharmacokinetic analysis was performed using a nonlinear mixed-effect population model. RESULTS: Data were modeled with a 1-compartment pharmacokinetic model. The population typical mean 90% confidence interval values for clearance, apparent volume of distribution (V), and duration of absorption (D1) were 6.8 L/h (range, 3.9-8.0 L/h), 159 L (range, 98.0-282 L), and 2 hours (fixed), respectively. The interindividual variability of clearance and V, and residual variability (90% confidence interval) were 74% (44%-96%), 69% (40%-89%), and 32% (20%-41%), respectively. The elimination half-life was 16 hours (range, 3-42 hours). CONCLUSIONS: Oxazepam exhibited a linear pharmacokinetics with a proportional relationship from 20 to 300 mg per day, the dose range currently used in alcohol-dependent patients treated for alcohol withdrawal syndrome. We did not find any evidence of drug accumulation with these doses.

Reinforcement of irritability during therapy with benzodiazepines.

BACKGROUND: Often, long-term treatment with benzodiazepines is a subject of discussion due to potential side effects, with dependence on benzodiazepines as the most serous one. After longer period of benzodiazepines tolerance on their anxiolytic effects develops. Discontinuation is usually beneficial as it is followed by improved psychomotor and cognitive functioning, particularly in the elderly. Previous studies confirmed occurrence of physical dependence in high percentage of patients in long term treatment with benzodiazepines at therapeutic dosages. Benzodiazepines are relatively well-tolerated medicines but can induce serious problems of addiction and that is why their use is regulated. The aim of this article is to report a case of a patient who was taking 15 tablets of oxazepam daily for a period of time, during which reinforcement of irritability occurred. CONCLUSION: It is necessary to warn patients who take benzodiazepines in therapy that reinforcement of irritability may occur in case of higher dosage of benzodiazepines, which may be misinterpreted as worsening in mental condition.

Alprazolam and oxazepam block the cue-induced reinstatement of extinguished cocaine seeking in rats.

RATIONALE: We have previously reported that pretreatment with benzodiazepines reduces intravenous cocaine self-administration in rats. OBJECTIVE: This experiment was designed to investigate whether or not benzodiazepines would also inhibit the reinstatement of cocaine seeking induced by the presentation of a conditioned reinforcer. MATERIALS AND METHODS: Adult male rats were implanted with jugular catheters and trained to self-administer cocaine (0.25 mg/kg/infusion) during daily 2-h sessions. During training, cocaine delivery was paired with the presentation of a tone and the illumination of a houselight. Once a stable baseline of cocaine self-administration was observed, lever pressing was extinguished to less than 20% of baseline rates. During reinstatement testing, responding resulted in the presentation of the conditioned reinforcer (i.e., the houselight and tone previously paired with self-administered cocaine). RESULTS: The response-contingent presentation of the conditioned reinforcer reliably reinstated cocaine seeking. Pretreatment with alprazolam (2 or 4 mg/kg, ip) or oxazepam (20 or 40 mg/kg, ip) reversed the conditioned reinforcer-induced reinstatement of extinguished cocaine-seeking behavior at doses that did not reliably affect the conditioned reinforcer-induced reinstatement of extinguished food seeking, suggesting that benzodiazepines may not have reduced reinstatement responding due to non-specific reductions in behavior. CONCLUSIONS: These data suggest that benzodiazepines may be useful in blocking the ability of environmental cues to stimulate cocaine seeking.

Effect of intranasal oxytocin on alcohol withdrawal syndrome: A randomized placebo-controlled double-blind clinical trial.

BACKGROUND: In a pilot study, intranasal oxytocin was demonstrated to reduce the benzodiazepine dose needed to relieve withdrawal symptoms during alcohol detoxification. The aim of the present study was to compare the effect of oxytocin and placebo during a three-day period of alcohol detoxification at an addiction treatment center in Norway. METHODS: Randomized, double-blind, placebo-controlled trial with 40 patients fulfilling criteria for ICD-10 diagnosis of alcohol dependence (F10.2), admitted for alcohol detoxification and withdrawal treatment. The benzodiazepine oxazepam was given as symptom-triggered treatment based on the scores of the Clinical Institute Withdrawal Assessment for Alcohol revised (CIWA-Ar) scale. Participants were randomized to receive either intranasal oxytocin (24 IU twice daily) or placebo. PRIMARY OUTCOME: Oxazepam dose required to complete a three-day course of detoxification. SECONDARY OUTCOMES: Scores of the CIWA-Ar, the 10-item Hopkins Symptom Check List (HSCL-10), and self-reported total number of hours of sleep. RESULTS: The mean total oxazepam dose (± standard deviation) was 56.8 ± 72.8 mg in the oxytocin group and 79.0 ± 122.9 in the placebo group (p = 0.490; difference -22.3 mg; 95% confidence interval (CI) -86.9 to +42.4 mg). The findings were inconclusive as to whether a difference in the CIWA-Ar score (5.94 ± 3.86 vs. 6.48 ± 3.92; p = 0.665) or in any of the other secondary outcomes was present. No serious adverse events were reported. CONCLUSION: Compared to placebo, intranasal oxytocin did not significantly reduce the oxazepam dose needed to complete a 3-day course of alcohol detoxification and withdrawal treatment.

Detection Time of Oxazepam and Zopiclone in Urine and Oral Fluid after Experimental Oral Dosing.

Data from previous experimental studies on the detection time of oxazepam and zopiclone in biological matrices are limited. The aim of this study was to examine the detection time in urine and oral fluid after single oral doses of oxazepam and zopiclone. Ten healthy volunteers received 25 mg of oxazepam in the evening of Day 1 and 7.5 mg of zopiclone in the evening of Day 3. Urine and oral fluid samples were collected twice daily for 9 days, with an additional sampling the day after ingestion of zopiclone. A total of 19 samples of both urine and oral fluid from each participant were analyzed using fully validated chromatographic methods. The median detection time for oxazepam was 91 h (range 73-108) in urine and 67 h (range 50-98) in oral fluid. The median detection time for zopiclone in urine was 49 h (range 25-98) and 59 h (range 48-146) in oral fluid. The metabolite zopiclone N-oxide showed a detection time of 36 h (range 25-84) in urine. The area under the concentration-time curve (AUCTotal) in urine corrected for creatinine was 150 µmol/L/mmol/L*h (range 105-216) for oxazepam and 1.60 µmol/L/mmol/L*h (range 0.79-4.53) for zopiclone. In oral fluid, the AUCtotal was 673 nmol/L*h (range 339-1,316) for oxazepam and 2,150 nmol/L*h (range 493-4,240) for zopiclone. In conclusion, oxazepam can be detected longer in urine than in oral fluid, while zopiclone can be detected longer in oral fluid than in urine. The high AUCTotal for zopiclone in oral fluid shows that the transfer into oral fluid is significant. In certain individuals the detection time of zopiclone in oral fluid is long. These results can be helpful when interpreting drug testing analyzes.

The concentration of oxazepam and oxazepam glucuronide in oral fluid, blood and serum after controlled administration of 15 and 30 mg oxazepam.

AIMS: To measure and compare the concentration-time profiles of oxazepam and oxazepam glucuronide in blood, serum and oral fluid within the scope of roadside testing. METHODS: Biological samples were collected from eight male subjects after ingestion of 15 or 30 mg oxazepam on separate dosing occasions with an interval of 7 days. The concentration-time profiles of oxazepam and oxazepam glucuronide were fitted by using a one-compartment model. RESULTS: For oxazepam and oxazepam glucuronide, the mean oral fluid/blood ratios were 0.05 (range 0.04-0.07) and 0.004 (range 0.002-0.006), respectively. The concentration-time profiles in oral fluid paralleled those in blood. CONCLUSION: After oral administration of therapeutic doses of oxazepam, concentrations in oral fluid are very much lower than those in blood, and those of oxazepam glucuronide are much lower than those of the parent compound. Nevertheless, assay of oral fluid for oxazepam can be used to detect recent ingestion of the drug in drivers suspected of impaired driving performance.

Relationship between dissolution efficiency of Oxazepam/carrier blends and drug and carrier molecular descriptors using multivariate regression analysis.

Quantitative structure-property relationships were developed for predicting the enhancement of dissolution rate of the model lipophilic drug Oxazepam (Oxa) from blends (BLs) with 12 structurally different carriers at three different drug/carrier weight ratios (1/5, 1/10, and 1/20). To this end, 36 BLs were prepared by the solvent-evaporation method and characterized by spectroscopic (FT-IR), thermoanalytical (DSC) and X-ray diffraction studies. The dissolution rate of the examined systems was quantified by logDE/DE(Oxa), where DE and DE(Oxa) are the dissolution efficiencies of the BL and pure drug, respectively. Twenty molecular descriptors, including parameters for size, lipophilicity, cohesive energy density (CED), and hydrogen bonding capacity were calculated and together with the experimental melting point (MP), were used in multivariate analysis. Twelve pertinent variables were detected after looking at the results of principal component analysis (PCA) and cluster analysis, and reliable six-descriptor models generated by Partial Least Squares-Projection to Latent Structures (PLS) method. Satisfactory coefficient of determination values were obtained (i.e., R(2) equal to 0.794 and Q(2) equal to 0.705). The equations generated can predict with reasonable accuracy the dissolution rate increase of the model lipophilic drug/carrier BLs.

An observational study of benzodiazepine prescription during inpatient alcohol detoxification for patients with vs. without chronic pretreatment with high-dosage baclofen.

High-dose baclofen is prescribed as a maintenance treatment to reduce alcohol use in patients with alcohol use disorder. Nevertheless, some patients still have massive alcohol intakes and require inpatient alcohol withdrawal. To compare the oral dose of benzodiazepine prescribed to manage alcohol withdrawal symptoms in patients with vs. without steady-state pretreatment with high-dose baclofen. Retrospective chart review study. Prescribed benzodiazepine dose expressed in diazepam-equivalent was compared between groups. Thirty-one patients were assessed in the high-dose maintenance baclofen group and compared to 31 matched patients not receiving baclofen. No statistically significant difference was evident between groups regarding levels of benzodiazepines prescribed. The mean diazepam-equivalent dose during the first 7 days was 294 ± 149 mg in the baclofen group vs. 310 ± 133 mg (t-test = 0.440, P = 0.661) in matched controls. Steady-state high-dose baclofen before an inpatient alcohol cessation hospitalization does not lower the needed benzodiazepine dose in the management of alcohol withdrawal symptoms.

Associations between use of benzodiazepines or related drugs and health, physical abilities and cognitive function: a non-randomised clinical study in the elderly.

OBJECTIVE: To describe associations between the use of benzodiazepines or related drugs (BZDs/RDs) and health, functional abilities and cognitive function in the elderly. METHODS: A non-randomised clinical study of patients aged > or =65 years admitted to acute hospital wards during 1 month. 164 patients (mean age +/- standard deviation [SD] 81.6 +/- 6.8 years) were admitted. Of these, nearly half (n = 78) had used BZDs/RDs before admission, and the remainder (n = 86) were non-users. Cognitive ability was assessed by the Mini-Mental State Examination (MMSE). Patients scoring > or =20 MMSE sum points were interviewed (n = 79) and questioned regarding symptoms and functional abilities during the week prior to admission. Data on use of BZDs/RDs before admission, current medications and discharge diagnoses were collected from medical records. Health, physical abilities and cognitive function were compared between BZD/RD users and non-users, and adjustments were made for confounding variables. The residual serum concentrations of oxazepam, temazepam and zopiclone were analysed. RESULTS: The mean +/- SD duration of BZD/RD use was 7 +/- 7 years (range 1-31). Two or three BZDs/RDs were concomitantly taken by 26% of users (n = 20). Long-term use of these drugs was associated with female sex and use of a higher number of drugs with effects on the CNS, which tended to be related to diagnosed dementia. After adjustment for these variables as confounders, use of BZDs/RDs was not associated with cognitive function as measured by the MMSE. However, use of BZDs/RDs was associated with dizziness, inability to sleep after awaking at night and tiredness in the mornings during the week prior to admission and with stronger depressive symptoms measured at the beginning of the hospital stay. Use of BZDs/RDs tended to be associated with a reduced ability to walk and shorter night-time sleep during the week prior to admission. A higher residual serum concentration of temazepam correlated with a lower MMSE sum score after adjustment for confounding variables. CONCLUSIONS: Long-term use and concomitant use of more than one BZD/RD were common in elderly patients hospitalised because of acute illnesses. Long-term use was associated with daytime and night-time symptoms indicative of poorer health and potentially caused by the adverse effects of these drugs.

Long v short half-life benzodiazepines in the elderly. Kinetics and clinical effects of diazepam and oxazepam.

Oxazepam and diazepam were compared in healthy elderly volunteers. Absorption of diazepam was faster than oxazepam and onset of clinical effects were more profound. Diazepam accumulation was extensive, washout was slow and active compounds were present two weeks after the last dose. Oxazepam accumulation was significantly less and elimination significantly faster than diazepam. There was no difference between oxazepam and diazepam in sedation or fatigue during the drug treatment, but sedative effects persisted for two weeks after diazepam therapy was discontinued. Sedation rapidly returned to baseline in the oxazepam group. Thus, the differing pharmacokinetic profiles of diazepam and oxazepam have clinical consequences during multiple dosage in the elderly.

Symptom-triggered vs fixed-schedule doses of benzodiazepine for alcohol withdrawal: a randomized treatment trial.

BACKGROUND: In alcohol withdrawal, fixed doses of benzodiazepine are generally recommended as a first-line pharmacologic approach. This study determines the benefits of an individualized treatment regimen on the quantity of benzodiazepine administered and the duration of its use during alcohol withdrawal treatment. METHODS: We conducted a prospective, randomized, double-blind, controlled trial including 117 consecutive patients with alcohol dependence, according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, entering an alcohol treatment program at both the Lausanne and Geneva university hospitals, Switzerland. Patients were randomized into 2 groups: (1) 56 were treated with oxazepam in response to the development of signs of alcohol withdrawal (symptom-triggered); and (2) 61 were treated with oxazepam every 6 hours with additional doses as needed (fixed-schedule). The administration of oxazepam in group 1 and additional oxazepam in group 2 was determined using a standardized measure of alcohol withdrawal. The main outcome measures were the total amount and duration of treatment with oxazepam, the incidence of complications, and the comfort level. RESULTS: A total of 22 patients (39%) in the symptom-triggered group were treated with oxazepam vs 100% in the fixed-schedule group (P<.001). The mean oxazepam dose administered in the symptom-triggered group was 37.5 mg compared with 231.4 mg in the fixed-schedule group (P<.001). The mean duration of oxazepam treatment was 20.0 hours in the symptom-triggered group vs 62.7 hours in the fixed-schedule group (P<.001). Withdrawal complications were limited to a single episode of seizures in the symptom-triggered group. There were no differences in the measures of comfort between the 2 groups. CONCLUSIONS: Symptom-triggered benzodiazepine treatment for alcohol withdrawal is safe, comfortable, and associated with a decrease in the quantity of medication and duration of treatment.

Renal disease, age, and oxazepam kinetics.

Effects of renal insufficiency and age on oxazepam kinetics were assessed in 13 normal subjects (21 to 72 yr old), four patients with renal insufficiency, and eight patients on hemodialysis. Normal intact oxazepam results were: mean elimination half-life (t1/2), 10 hr; area under the curve (AUC), 6.0 microgram.hr/ml; unbound oxazepam fraction (fup), 3.2%; maximum concentration of unbound oxazepam (Cmax,u), 16 ng/ml; and intrinsic (unbound drug) clearance (Clint), 2.9 l/hr/kg. Less than 1% of the dose was excreted intact in urine. Age differences had no influence on results. In renal insufficiency patients, t1/2 was prolonged to 25 hr, fup increased to 7%, and Cmax,u and Clint were unchanged. Volume of distribution of unbound oxazepam (Vu) increased, thereby prolonging t1/2. In dialysis patients, t1/2 was prolonged to 33 hr, fup increased to 6.2%, and Cmax,u and Clint again were unchanged. Oxazepam was undialyzable; since unbound oxazepam disposition kinetics are not altered, no dosage adjustment for patients is necessary.

Self-administration of clonidine, oxazepam, and hydromorphone by patients undergoing methadone detoxification.

The extent to which hydromorphone, clonidine, and oxazepam alleviate the symptoms of opioid withdrawal and the extent and pattern of self-administration of these drugs during methadone detoxification were examined within a residential laboratory in three groups of patients dependent on methadone. Six times over the course of detoxification, acute effects of orally administered placebo and a single active drug (hydromorphone HCl, 3 mg, clonidine HCl, 0.3 mg, or oxazepam, 30 mg, all given twice daily) were tested, followed by an opportunity for subjects to self-administer the drug and dose of their choice. Hydromorphone significantly decreased opioid withdrawal symptoms and was more preferred for self-administration than the placebo. Clonidine and oxazepam did not significantly decrease withdrawal symptoms, nor was either drug self-administered significantly more than placebo. Clonidine, however, did induce side effects.

Massive benzodiazepine requirements during acute alcohol withdrawal.

Severe alcohol withdrawal developed in an abstinent chronic alcoholic man. Massive doses of benzodiazepines (2,335 mg of diazepam intravenously, 21,225 mg of oxazepam orally) achieved only marginal control of delirium and agitation. Analysis of multiple blood samples drawn during and after the withdrawal episode indicated, as expected, very high concentrations of diazepam and metabolites and of oxazepam. There was no evidence of an abnormal pharmacokinetic profile. Benzodiazepine resistance in withdrawing alcoholics probably reflects a receptor-site phenomenon rather than an abnormal drug disposition.

Oxazepam esters. 3. Intrinsic activity, selectivity, and prodrug effect.

Antimetrazol and muscle-relaxant activities of 11 aliphatic esters of oxazepam were studied as a function of time in mice. The esters given intravenously retained antimetrazol activity, while muscle-relaxant activity was generally decreased. The administration of a dose equivalent to the antimetrazol ED50 resulted in constant oxazepam brain levels for most esters; therefore, the intrinsic anticonvulsant activity of the intact ester is insignificant. The dimethylphenylpropionyl ester appeared to antagonize the effect of oxazepam, since it elevated the free oxazepam level required to achieve the ED50 in the antimetrazol assay. The administration of doses equivalent to the muscle-relaxant ED50 values resulted in no correlation with total brain benzodiazepine levels, suggesting that changes in the selectivity of action are the consequence of different sites of action.

Clinical pharmacokinetics of oxazepam and lorazepam.

Oxazepam and lorazepam are 3-hydroxy benzodiazepine derivatives used as sedatives and anxiolytics. The major metabolic pathway for both compounds involves conjugation to glucuronic acid at the 3-position, followed by urinary excretion of the inactive glucuronide metabolite. Oxazepam has been administered to humans by the oral route only. Usual ranges for kinetic parameters are: elimination half-life, 5 to 15 hours; volume of distribution, 0.6 to 2.0 L/kg; clearance, 0.9 to 2.0 ml/min/kg. Age and liver disease have a minimal influence on oxazepam kinetics, but renal disease is associated with a prolonged half-life and increased volume of distribution. Typical kinetic values for lorazepam are: elimination half-life, 8 to 25 hours; volume of distribution, 1.0 to 1.3 L/kg; clearance, 0.7 to 1.2 ml/min/kg. Lorazepam clearance is somewhat reduced in old age, but liver disease has a minimal effect on clearance. Oral and intramuscular lorazepam are rapidly absorbed, with systemic availability averaging 90% or more. Both oxazepam and lorazepam are extensively bound to plasma protein, but the free fraction for lorazepam (8 to 12%) is greater than that for oxazepam (2 to 4%).

Pharmacodynamics of the anticonvulsant effect of oxazepam in aging BN/BiRij rats.

1. The purpose of this investigation was to examine the influence of increasing age on the pharmacokinetics and the time course of the anticonvulsant response of oxazepam in BN/BiRij rats as an animal model of aging. 2. Oxazepam was administered intravenously in a dose of 12 mg kg-1 body weight and the anticonvulsant effect intensity was measured as elevation above baseline of a threshold for induction of localized seizure activity (TLS). Direct cortical stimulation with ramp shaped electrical pulse trains of increasing intensity was used to determine this threshold. 3. The pharmacological effect vs. time profile showed in young rats an anticonvulsant component followed by proconvulsant component which is suggestive for the occurrence of acute tolerance and/or withdrawal syndrome. With increasing age the proconvulsant component disappeared, resulting in a monophasic effect profile (anticonvulsant effect only) at the age of 35 months with significantly higher anticonvulsant effect intensity immediately following drug administration. No age-related changes in the pharmacokinetic parameters of oxazepam were observed. 4. In five animals of each age group, benzodiazepine receptor binding characteristics were determined in vitro with [3H]-flunitrazepam as a ligand. Both receptor density and affinity did not show age-related changes. Available literature data on post-receptor events do not indicate conclusive age-related changes. 5. It is concluded, that the observed change in the pharmacodynamics of anticonvulsant effect of oxazepam can be explained by the disappearance of the tolerance/withdrawal phenomenon. This is compatible with a decreased efficiency of homeostatic control mechanisms in the elderly.

A double-blind, controlled trial in primary care patients with generalized anxiety: a comparison between buspirone and oxazepam.

Two hundred thirty patients with generalized anxiety and Hamilton Rating Scale for Anxiety (HAM-A) scores greater than or equal to 18 were subdivided at random, according to a double-blind design, into one group treated with 5-10 mg of oral buspirone t.i.d. or one group treated with 10-20 mg of oral oxazepam t.i.d. for 6 weeks. No anxiolytic treatment was allowed 3 months prior to trial entry. Analysis of demographic variables revealed no significant imbalance between the two treatment groups. Twenty patients were excluded from efficacy analysis because of treatment withdrawal before the first efficacy evaluation on Day 7. Another 4 patients were excluded because they were taking concomitant psychotropic medication. The remaining 206 patients displayed a decrease in HAM-A scores (mean +/- SD) from 23.9 +/- 4.1 to 10.6 +/- 7.7 in the buspirone group and from 23.9 +/- 4.2 to 11.5 +/- 8.0 in the oxazepam group. The two treatment groups were also found to be virtually identical in an "intent to treat" analysis of all 230 patients as well as in other ratings (Hamilton Rating Scale for Depression, Raskin Depression Scale, Covi Anxiety Scale, Physicians Questionnaire, global ratings, and Hopkins Symptom Checklist [HSCL]-56). However, oxazepam was never superior to buspirone in any of the efficacy analyses. Of the 230 patients, 127 spontaneously reported adverse events, including drowsiness, dizziness, headache, nausea, and nervousness. Adverse events were relatively similar in the two groups. In conclusion, buspirone and oxazepam appear to be equally effective in the treatment of generalized anxiety encountered by general practitioners. This outcome, in addition to a previously documented absence of any dependency liability, makes buspirone a clinically important anxiolytic drug.