Clobazam as a New Antiepileptic Drug and Clorazepate Dipotassium as an Alternative Antiepileptic Drug in Japan

PURPOSE

To confirm the efficacy and to clarify the problems of clobazam (CLB) as a new antiepileptic drug (AED) and clorazepate (CLP) as an alternative AED in Japan.

METHODS

CLB and CLP were added on or replaced with conventional AEDs in 55 and 170 patients with refractory epilepsies, respectively. Short-term efficacy was studied after at least 2 months of CLB administration and at least 4 weeks of CLP administration. Long-term efficacy was examined in 31 cases with CLB for > or =6 months and in 86 cases with CLP for > or =6 months. CLB was initiated at 0.15-0.40 mg/kg and increased by 0.1-0.2 mg/kg every 1-2 weeks up to 0.28-1.25 mg/kg. CLP was started at 0.3-0.7 mg/kg and increased by 0.2-0.3 mg/kg every 1-2 weeks up to 2.5 mg/kg. Tolerance was examined in 42 cases with CLB for > or =3 months and 112 cases with CLP for > or =4 weeks.

RESULTS

CLB was effective, defined as > or =50% reduction in seizure frequency, in 71% of the short-term subjects and 81% of the long-term subjects. Short-term efficacy was better in symptomatic localization-related epilepsies, but long-term efficacy did not differ according to seizure classification. Short-term efficacy was not different by seizure types or EEG findings. CLP was effective in 70% of the short-term subjects and 80% of the long-term subjects. CLP was more effective in patients with localization-related epilepsies or in patients with partial seizures or focal epileptiform discharges on EEG. Adverse effects developed in 47% of CLB cases and 31% of CLP cases, but the incidence was reduced by lower initial doses and slow dose titration. Tolerance occurred in 24% of CLB cases and 48% of CLP cases, half within 3-4 months after the initiation of CLB and half by 2 months after the start of CLP. Upon rechallenge, 70% of CLB-tolerant cases and 50% of CLP-tolerant cases responded to each drug again by increasing or maintaining the dosage.

CONCLUSIONS

Excellent efficacy of CLB and excellent and prolonged efficacy of CLP for refractory epilepsies were confirmed. Frequent tolerance and adverse effects were major problems, but were manageable.

Clorazepate dipotassium versus midazolam for premedication in clear corneal cataract surgery

PURPOSE

To evaluate and compare the efficacy of oral clorazepate dipotassium (Tranxilium) and intravenous midazolam (Dormicum) as premedication agents in retrobulbar anesthesia and clear corneal phacoemulsification with intraocular lens (IOL) implantation.

SETTING

Department of Ophthalmology, University of Essen, Essen, Germany.

METHODS

In a prospective clinical trial, 97 consecutive patients (97 eyes) having phacoemulsification with implantation of a foldable IOL were randomized to 2 groups. The first group received 10 mg oral clorazepate dipotassium and the second group, 1 mg intravenous midazolam. The surgeon's subjective experience of patients' cooperation during retrobulbar anesthesia and after surgery was measured on a 5-point Likert scale. The duration of surgery and rate of complications were documented. One day after surgery, the patients' subjective comfort during cataract surgery was evaluated using a 5-point Likert scale and the best corrected visual acuity was determined.

RESULTS

The level of anterograde amnesia tended to be higher in the midazolam group than in the clorazepate dipotassium group (4% versus 0% for anesthesia administration; 14% versus 4% for surgery), but the difference between groups was not significant. There were no significant differences in patient cooperation or complications during surgery. Patient satisfaction scores were not significantly different between the groups (P<.14); however, patients in the midazolam group expected to have significantly less pain during surgery (P<.04). The rate of potential visual acuity recovery was similar between groups.

CONCLUSIONS

Anterograde amnesia occurred more frequently and patients expected less pain before surgery with midazolam. Both anesthetic agents provided safe and effective premedication for retrobulbar anesthesia in clear corneal cataract surgery.

In vitro drug allergy detection system incorporating human liver microsomes in chlorazepate-induced skin rash: drug-specific proliferation associated with interleukin-5 secretion

BACKGROUND

Chlorazepate is a benzodiazepine often used for pre-operative anxiolysis. The central metabolite responsible for the pharmacological and probably for the adverse effects of most benzodiazepines, including chlorazepate, is N-desmethyldiazepam. We report a woman who developed a generalized exanthem 1 day after receiving chlorazepate and four other drugs related to anaesthesia for surgery of the larynx. Patch tests pointed to chlorazepate as the culprit drug for the skin rash.

OBJECTIVES

The purpose of this study was to detect drug allergy to chlorazepate or a metabolite in vitro by means of the lymphocyte transformation test (LTT), and to determine the concentrations of the T-helper (Th) 2-type cytokine interleukin (IL)-5 and the Th1-type cytokine interferon (IFN) -gamma in the culture supernatants.

METHODS

We performed an LTT with peripheral blood mononuclear cells from the patient and a control, employing human liver microsomes containing cytochrome P450 enzymes as a metabolizing system, in parallel cultures. IL-5 and IFN-gamma concentrations in the culture supernatants were assessed by enzyme-linked immunosorbent assay.

RESULTS

In the LTT, no T-cell reactivity was observed to the parent compound chlorazepate, whereas coincubation of the drug with human liver microsomes yielded proliferative T-cell reactivity, which was associated with secretion of IL-5 but not of IFN-gamma.

CONCLUSIONS

We conclude that addition of a metabolizing system may be advantageous for in vitro detection of T-cell reactivity to drug metabolites in the LTT.

Comparative study of the efficacy and safety of trazodone versus clorazepate in the treatment of adjustment disorders in cancer patients: a pilot study

The efficacy of trazodone (mean once-daily dose 111.5 +/- 36.3 mg) versus clorazepate (mean once-daily dose 17.5 +/- 7.5 mg) to relieve anxious and depressive symptoms in 18 patients undergoing treatment for breast cancer was investigated in a 28-day randomized, double-blind study. Efficacy was evaluated using the Hospital Anxiety and Depression Scale, the Revised Symptom Checklist and the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire. A successful response to treatment was achieved in 91% (10/11) of patients who received trazodone and 57% (four of seven) of patients who were administered clorazepate (P = 0.1373). Bayesian analysis revealed that the prior probability of making a wrong decision in prescribing trazodone rather than clorazepate reduced from 26% to 8%. Assessment of the clinical scales suggested a benefit of trazodone compared with clorazepate, although the differences were not significant. Safety of both treatments was similar. Trazodone is devoid of an abuse risk and dependence and, therefore, could be a valuable alternative to clorazepate in the treatment of adjustment disorders in cancer patients.

Effect of dipotassium clorazepate on amygdaloid-kindling and comparison between amygdaloid- and hippocampal-kindled seizures in rats

We examined the effect of dipotassium clorazepate (7-chloro-1, 3-dihydro-2-oxo-5-phenyl-1H-1, 4-benzodiazepine-3-carboxylate potassium hydroxide), an antianxiety drug, on amygdaloid kindling and compared its effects for 7 successive days on amygdaloid- versus hippocampal-kindled seizures, using the rat kindling model of epilepsy. Dipotassium clorazepate at 5 mg/kg significantly delayed amygdaloid kindling. The contralateral cortical after-discharge duration in the dipotassium clorazepate-treated group was significantly shorter than the after-discharge duration in the amygdala in the first seven stimulations, whereas it was significantly shorter only in the first three stimulations in the control group, indicating that dipotassium clorazepate suppressed the spread of seizure activity from focus to contralateral cortex. Dipotassium clorazepate suppressed amygdaloid-kindled seizures at 2 and 5 mg/kg, while 1 mg/kg or more suppressed hippocampal-kindled seizures. Thus, differences in effective dosages in both amygdaloid- and hippocampal-kindled seizures may suggest a difference in the neuronal mechanisms involved in this kindling.

Prolonged sedation requiring mechanical ventilation and continuous flumazenil infusion after routine doses of clorazepam for alcohol withdrawal syndrome

We report the cases of two patients who developed prolonged sedation after routine doses of clorazepam for alcohol withdrawal syndrome. They required prolonged mechanical ventilation (10 days for both patients) followed by continuous flumazenil infusion (16 days for one patient and 3 days for the other) to avoid reintubation. In the two patients, nordazepam accumulation (main active metabolite of clorazepam) was demonstrated as the cause of the coma. This accumulation could be attributed, in one case, to impaired hepatic cytochrome P 450 3A4 activity. Caution is required when prescribing benzodiazepines to alcoholic patients and the use of benzodiazepine which do not undergo hepatic oxidation by cytochrome P 450 such as oxazepam or lorazepam is suggested.

Efficacy and safety of trazodone versus clorazepate in the treatment of HIV-positive subjects with adjustment disorders: a pilot study

The efficacy of trazodone and clorazepate to relieve anxiety and depressive symptoms in 21 HIV-positive subjects with adjustment disorders was determined in a 28-day single-centre, randomized, double-blind study. Subjects were evaluated using the Hospital Anxiety and Depression Scale, the Revised Symptom Checklist, the European Organization for Research and the Treatment of Cancer Quality of Life Questionnaire, and a binary criterion based on the Clinical Global Impression. The incidence of successful treatment was 80% for trazodone compared with 64% for clorazepate; the sample number was too small to establish a significant difference. Bayesian analysis revealed the probability of making a wrong decision in prescribing trazodone rather than clorazepate reduced from 35% to 18% in this small sample. Clinical evaluations using the different scales suggest some benefit from trazodone, although this was not significant. Safety of both treatments was similar. Trazodone is devoid of the risk of abuse and dependence, and may be a valuable alternative to benzodiazepines for the treatment of HIV-related adjustment disorders.

[Optimizing anesthesiologic premedication with reference to biopsychological theories. Exemplified by the effect of dipotassium clorazepate and zolpidem in combination with promethazine]

The following double-blind randomized placebo-controlled study dealt with three questions: 1. Are differentiated psychometric test systems suitable measuring emotions before anaesthesia? 2. What are the effects of different doses of zolpidem (8.03 mg vs. 16.06 mg) compared with dipotassiumclorazepat (10 mg vs. 20 mg) on emotions in premedication? 3. Is the combination with Promethazin suggestive?

METHOD

320 patients were randomly assigned to different regimes of preanaesthetic medication. As primary premedication they received either zolpidem 8.03 mg or zolpidem 16.06 mg or dipotassium clorazepate 10 mg or dipotassium clorazepate 20 mg or placebo. The secondary premedication was either promethazine 50 mg or placebo. The tablets/dragees were given in the evening before surgery (09.00 p.m.-10.00 p.m.). Every cell of the 5 x 2-factorial design contained 16 men and 16 women. Emotions were measured by a multidimensional rating scale, comprising the aspects elated mood, anxiety, hostility, deactivation, vigilance and introversion. In addition, somatic symptoms and the quality of sleep were measured. Statistics were performed using multivariate analysis of variance.

RESULTS

No differing effects of zolpidem and dipotassium clorazepate on preoperative mood were found. There was also no difference compared with placebo. Compared with placebo, promethazin leads to greater deactivation. Specific emotions were not affected. In somatic aspects there was a greater amount of cholinergic effects under promethazine, which was mainly expressed by a higher intensity of a dry mouth and weakness in general. Compared with placebo all of the tested drugs led to a better quality of sleep.

CONCLUSIONS

Using multidimensional rating scales and considering emotions as a multifactorial construct, the study shows no different effects of benzodiazepines or benzodiazepin-like drugs on preoperative mood. No differences were also found on comparing these drugs with placebo. However, a better quality of sleep was seen under zolpidem and dipotassium clorazepate compared with placebo. The study shows that a combination with promethazine is recommended, because promethazine has a selective deactivating effect. The study stresses the significance of multidimensional rating scales for the measurement of emotions before anaesthesia.

[Porphyria variegata. Apropos of a case]

A patient hospitalized because of somatic disturbances without any sign of detectable cerebral organicity and because of secondary anxiety disorder and major depression presents different clinical pictures with a neurological aspect. All this pictures, that evoke the diagnostic of hysteria conversion in particular, are complicated by a tetraplegia with emission of red urine that enable us to think of a diagnostic of hepatic-porphyria (variegata). Hereditary metabolic diseases, which categories of bioclinic symptoms (that enable us to evoke the diagnostic and to prevent the complications that are breeded by the prescription of forbidden drugs for ill subject) are reminded.

Hypoxaemia and myocardial ischaemia on the night before coronary bypass surgery

Using pulse oximetry and Holter ECG monitoring on the night before coronary bypass surgery, we studied 30 male patients with coronary artery disease to determine the relationship between nocturnal hypoxaemia and myocardial ischaemia. The patients received intensive anti-angina medication and were sedated with clorazepate. Ten patients developed a total of 42 ischaemic episodes, 24 of which occurred between 22:00 and 06:00. Mean heart rate was significantly higher in patients with ischaemia than in those without ischaemia. In 60% of all patients, heart rate increased > or = 20% at the onset of the ischaemic episode. The patients spent a median of 2 (range 0.02-40.6)% of the night with oxygen saturation (SpO2) < 90% (the minimum SpO2 value recorded was 84 (69-88) %). Only five ischaemic episodes were associated with respiratory events. These were not associated with either extraordinary oxygen desaturation or marked increases in heart rate. Comparing patients with and without ischaemia, there were no significant differences in the extent of nocturnal hypoxaemia or the pattern of desaturation episodes (cyclic variations in saturation characteristic of periodical breathing vs non-cyclic desaturation episodes). Despite marked nocturnal hypoxaemia, simultaneous occurrence of desaturation episodes and myocardial ischaemia was a rare event in our study.

Case study of neuroleptic-induced akathisia: important implications for individuals with mental retardation

Neuroleptic-induced akathisia is a relatively common side effect of neuroleptic medication, characterized by a subjective sense of restlessness and the inability to sit still. It has been associated with aggression, anxiety, sleep disturbance, and suicide among patients who have mental illness. These side effects are fairly well-researched in the psychiatric literature but rarely addressed in the mental retardation literature. The prevalence, types of akathisia, differential diagnosis, and treatment were reviewed and a relevant case report presented. The importance of the diagnosis and treatment of neuroleptic-induced akathisia in individuals with mental retardation was discussed.

Treating anxiety while minimizing abuse and dependence

Anxiety is common and often disabling. Although effective treatments are available, the use of antianxiety medication remains controversial. Some of the controversy involves the relative benefits of psychological versus pharmacologic interventions. Much of the expressed concern, however, relates to the risks of abuse and dependence associated with standard antianxiety drugs. In some instances, concern about these risks prevents patients from receiving potentially effective treatment. In other instances, failure to recognize possible abuse and dependence results in a clinical dilemma. This presentation will address the factors involved in anxiolytic drug dependence and abuse, including patient characteristics and the pharmacologic profiles of anxiolytic drugs. Specific recommendations about how to minimize abuse and dependence through such measures as diagnostic assessment, patient education, drug selection, and treatment planning will be offered.

A post-marketing surveillance survey on the use of dipotassium clorazepate in clinical practice in the Philippines

A post-marketing surveillance survey of dipotassium clorazepate usage was carried out in the Philippines between July 1990 and April 1991. Data were analyzed on 562 patients suffering from conditions in which anxiety was a major component. The results suggest that the medication was prescribed in accordance with the generally accepted best practice for benzodiazepines. Overall, 85% of patients were reported to have recovered and only 2% reported minor side-effects. Dipotassium clorazepate was thus confirmed to be a highly effective and relatively safe anxiolytic agent.

[Treatment of delirium tremens--a comparison between clomethiazole and clorazepate with reference to effectiveness and rate of side effects]

In an open clinical trial patients with full-developed delirium tremens were treated either by controlled infusion of clomethiazol (n = 21) or by intravenous injections of clorazepate (n = 20). Acute symptomatic quickly decreased after a few days and medication could be reduced. By adding haloperidol a further stabilization in patients suffering from vivid hallucinations could be obtained. The duration of intravenous therapy and the total period of treatment did not differ in the two groups. Statistical analysis of cardiovascular parameters revealed a significant lower heart rate under clorazepate therapy. So treatment with clorazepate proved to be an alternative to standard therapy with clomethiazol even for severe cases of delirium tremens regarding its wide therapeutical range and the low rate of cardio-pulmonary complications.

[A comparative study of the efficacy and tolerance of dipotassium clorazepate and flunitrazepam for oral premedication]

The literature shows that benzodiazepines, in view of their anxiolytic, sedative, amnesic, muscle relaxant and anticonvulsive action, are the most important substances for premedication. Eminent workers regard anxiolysis as the most important aim of premedication. In the present clinical study, oral administration of the two different benzodiazepine derivatives, flunitrazepam (F) and chlorazepate dipotassium (CD) have been explored with a view to side effects, tolerance, quality of sleep during the night, anxiolytic effect and sedation. The study involved 108 women patients aged from 20 to 60 years (ASA class I or II), all scheduled to undergo gynecological surgery in general anesthesia. There were also 20 women who received no premedication. The three groups of patients were further divided into early (operation started before 10:30 a.m.) and late-operation (operation started after 10:30 a.m.) groups. The test drugs were administered as follows: 43 women received 50 mg CD p.o. on the evening before the operation, followed by 25 mg p.o. in the morning; 45 women received 2 mg F p.o. on the evening before the operation, followed by 1 mg p.o. in the morning. All patients took the preoperative premedication at 7 o'clock in the morning. Following this medication, the anxiolytic, sedative, and amnesic effects, side effects, vigilance and O2 saturation (SaO2) were determined at defined points during the day of the operation and the 1st postoperative day. Blood pressure and heart rate were recorded and interpreted as physiological stress parameters. Anxiolysis was determined using the Erlangen Anxiety Scale (EAS) of Galster and Spörl; the degree of sedation was assessed by the anesthesiologist; amnesia was determined by the patients' recognition of picture cards; vigilance and side-effects were assessed by standardized questionnaires. Both active drugs clearly improved the quality of sleep in the night before the operation over that experienced with no premedication. There were no significant differences among the three groups in the physiological stress parameters. The preoperative SaO2 saturation was decreased significantly by oral F, but it was always more than 95%. CD had little influence on the SaO2. Unwanted somatic symptoms were found a little more frequently in the group without any premedication. There were no signs of restricted tolerance for either of the test drugs. In the premedicated groups, pre- and postoperative anxiety decreased significantly.(ABSTRACT TRUNCATED AT 400 WORDS)

Benzodiazepine withdrawal delirium with catatonic features. Occurrence in patients with partial seizure disorders

We report the cases of 3 patients with medically intractable seizures in whom withdrawal of treatment with a long-acting benzodiazepine (clorazepate dipotassium, 2 patients; clonazepam, 1 patient) was followed by delirium with catatoniclike features. While an increase in seizure frequency occurred during withdrawal and prior to the onset of behavioral changes, electroencephalograms did not show epileptiform activity during the delirium. We compared these 3 patients with 10 others with intractable seizures in whom antiepileptic therapy was withdrawn without subsequent behavior changes. High-dose benzodiazepine therapy and a history of viral encephalitis may be risk factors for withdrawal delirium.

Depressive symptoms and intellectual functioning in anxiety patients treated with clorazepate

The combined data from two 1970s anxiety studies that used clorazepate and placebo as controls were reanalyzed statistically with a focus on intellectual functioning and depressive symptoms. For the 176 patients given either clorazepate or placebo, significant improvement was observed on the mean scores of the intellectual item and the depressive item of the Hamilton Rating Scale for Anxiety; the clorazepate group was significantly more improved than the placebo group. Similar results were observed in patients' self-ratings. The authors conclude that clorazepate is effective in treating depressive symptoms and improving intellectual functioning in patients with generalized anxiety disorder.

Long-term treatment of anxiety and risk of withdrawal. Prospective comparison of clorazepate and buspirone

Risk of withdrawal was investigated in a prospective, double-blind comparison of clorazepate dipotassium, a benzodiazepine with a long half-life, and the nonbenzodiazepine buspirone hydrochloride in the long-term treatment of anxious outpatients. Patients were treated with therapeutic doses of clorazepate dipotassium (15 to 60 mg/d) or buspirone hydrochloride (10 to 40 mg/d) for six continuous months before their tranquilizer therapy was blindly and abruptly stopped. There was a significant increase in symptom severity consistent with a withdrawal reaction for the clorazepate group but not the buspirone group. For the clorazepate group, there was a suggestion that previous discontinuous exposure to benzodiazepines might sensitize patients to subsequent withdrawal effects. For the buspirone group, a higher dropout rate raised questions about patient satisfaction with therapy in this rather chronically anxious population.

Clorazepate and lorazepam: clinical improvement and rebound anxiety

Sixty-two anxious patients were treated under double-blind conditions for 4 weeks with either clorazepate or lorazepam. Two-thirds of each treatment group were then switched abruptly to placebo for 2 weeks, while one-third continued to receive active medication. Two major findings were obtained. About 70% of the patients maintained improvement during the 2-week placebo period. Some patients, however, experienced rebound anxiety, which appeared to be more intense and occurred earlier when placebo was substituted for a benzodiazepine with a short half-life (lorazepam) than for one with a long half-life (clorazepate). The clinical relevance of these findings is discussed.

Clorazepate therapy for intractable epilepsy

Thirty-one epileptic patients with seizures refractory to conventional anticonvulsants were treated by adding clorazepate dipotassium to their regimen. Twelve cases showed improvement in seizure frequency, three of whom attained a seizure free state. Response to clorazepate was not related to the type of epilepsy, but patients with secondary generalized epilepsy tended to be less responsive than those with partial epilepsy. Among the various seizure types, generalized tonic-clonic seizures and simple partial seizures showed, although not significant, a tendency to be more responsive to clorazepate therapy than other seizure types, including complex partial seizures, atypical absence, atonic seizures, and tonic seizures. Drowsiness was the main adverse effect, of which 14 patients complained. Six patients were withdrawn from clorazepate because of drowsiness, but in the remaining 8 patients, this side effect disappeared within a week. The appearance of adverse effect was not related to the dose of clorazepate given. Clorazepate may be an effective secondary anticonvulsant in the treatment of intractable epilepsy.

Review of the side-effect profile of buspirone

In 984 patients with generalized anxiety disorder who received buspirone in double-blind studies, the incidence of drowsiness (9 percent) did not differ significantly from that (10 percent) reported in 334 patients who received placebo. A probability value of p less than or equal to 0.10 was the criterion for significance. The incidence of drowsiness in buspirone-treated patients was significantly less than that in each of the groups receiving diazepam (32 percent), clorazepate (26 percent), lorazepam (58 percent), or alprazolam (43 percent). The side effects that did occur significantly more frequently in the buspirone group than in the placebo group were dizziness (9 percent versus 2 percent), headache (7 percent versus 2 percent), nervousness (4 percent versus 1 percent), light-headedness (4 percent versus less than 1 percent), diarrhea (3 percent versus less than 1 percent), paresthesia (2 percent versus less than 1 percent), excitation (2 percent versus less than 1 percent), and sweating/clamminess (1 percent versus 0 percent). The severities of these effects were predominantly rated as only mild or moderate. Fatigue occurred less frequently in buspirone-treated patients than in those receiving any of the benzodiazepines, and weakness occurred more frequently in diazepam-treated patients. Depression occurred less frequently in buspirone-treated patients than in those receiving clorazepate, diazepam, or lorazepam. Impotence occurred only in clorazepate- and lorazepam-treated patients. Decreased libido occurred more frequently in diazepam-treated patients, whereas increased libido was more frequent in clorazepate-treated patients. Nausea was reported more frequently in buspirone-treated patients than in those receiving clorazepate, diazepam, or alprazolam; diarrhea occurred more frequently in the buspirone group than in the diazepam group. The mean daily doses of the various treatments were buspirone, 20 mg; diazepam, 20 mg; clorazepate, 24 mg; lorazepam, 3 mg; and alprazolam, 1.5 mg. In an open-field study in West Germany involving 5,414 patients, gastrointestinal-related complaints were the most frequently reported side effects.

Double-blind comparison of buspirone and clorazepate in anxious outpatients

Buspirone, a new nonbenzodiazepine anxiolytic agent, was compared with clorazepate in a double-blind, multicenter trial conducted with 336 outpatients who had moderate to severe anxiety. The two treatments were equally effective for relief of symptoms, including anxiety with associated depression. Although both agents were generally well tolerated, the profile of side effects was dissimilar. Drowsiness and depression occurred significantly (p less than 0.055) more frequently with clorazepate, whereas nausea and headache occurred significantly (p less than 0.055) more frequently with buspirone. Clorazepate-treated patients were significantly (p less than 0.055) more likely to have had an adverse experience that was considered drug related or that interfered with the therapeutic effect. In this study, buspirone was shown to be an effective antianxiety agent, causing significantly less sedation than clorazepate.

Efficacy of second line antiepileptic drugs in the treatment of patients with medically refractive complex partial seizures

The efficacy of second-line antiepileptic drugs (AEDs) was evaluated in the treatment of 66 patients with complex partial seizures who had previously failed first-line AEDs. Methsuximide, valproate, or clorazepate had eliminated seizures in 11% of the patients at the end of the study. However, these good results deteriorated on longer follow-up and were not expected to be permanent. It is recommended that suitable patients with partial epilepsy be referred for surgical evaluation after failing the first-line AEDs, and that second-line AEDs be reserved for nonsurgical candidates.

Chronic use of benzodiazepines and psychomotor and cognitive test performance

The performance of 43 long-term users (average = 5 years) of benzodiazepine (BZ) medications was examined on a battery of behavioral tasks, cognitive tests, and subjective mood rating scales. The performance of the chronic BZ users did not differ significantly from age- and sex-matched anxious subjects, except that critical flicker fusion (CFF) thresholds were lower and subjective ratings of tranquilization were higher in the BZ users. Twenty-two subjects were reexamined in order to determine the acute effects of BZ medications in long-term users. The acute administration of BZ medications significantly increased CFF thresholds, improved digit-symbol substitution test performance, impaired the delayed recall of verbal material, increased subjective ratings of tranquilization, and reduced physical sedation. Motor performance tests were not impaired and subjective feelings of sedation were not increased after the acute administration of BZs by chronic users. During withdrawal from long-term BZ use (17 subjects), CFF thresholds were elevated, subjective ratings of physical sedation and anxiety were increased, but performance on other psychomotor and cognitive tests was not altered. The results suggest that tolerance develops selectively to different behavioral and subjective effects of BZ medications with their continued use. Tolerance failed to develop to the antianxiety effects, the reduction of CFF threshold, and to the impairment of short-term memory caused by BZs. However, chronic users of BZ medications failed to demonstrate psychomotor-impairing or sedating effects to BZ medications. The results have implications for evaluating the safety of the long-term use of BZ medications.

Effects of clorazepate dipotassium and placebo on psychomotor skills

24 normal, healthy subjects were assigned randomly to 15 mg clorazepate dipotassium or placebo groups in a double-blind study. Their performance on a psychological test battery was assessed 45 min. later. Clorazepate dipotassium produced statistically significant impairment in attention and simple reaction time compared with placebo. Performance on more complex tests of cognitive functioning showed no drug effects.

Lack of amnestic effects of clorazepate on geriatric recall

Significant amnestic effects in young adults have been found with the short-acting sedative-hypnotic triazolam and the intermediate-acting lorazepam, but not with the longer-acting clorazepate. The effects of placebo and clorazepate 3.75 and 7.5 mg were compared in 43 nonanxious geriatric subjects. Results were consistent with earlier studies, and no significant impairment of immediate or delayed recall was found.

Fatal complications of neuroleptic drugs. A clinico-pathological study of three cases

We report three cases of fatal hyperthermia in the course of neuroleptic drug treatment. One patient developed his symptoms within hours after a single drug dose whereas the two others had a prolonged symptomatology which lasted for several days after the administration of different neuroleptic drugs. Biochemical events included diffuse intravascular coagulation, muscle cell necrosis and acute renal failure. Rhabdomyolysis was proved pathologically in two patients but brain lesions were atypical in all three cases. We conclude that the biochemical and pathological abnormalities seen in these patients are those which have been described by some authors in the malignant hyperthermia syndrome after anaesthesia. The symptomatology however can be insidious and the syndrome can develop after withdrawal of the drugs.

The side effect profile of buspirone in comparison to active controls and placebo

Animal studies and the original study comparing buspirone with diazepam and placebo indicated that sedative-hypnotic side effects and impairment in psychomotor function would be less with buspirone than with diazepam. This was borne out by the present double-blind study in which almost 700 patients received buspirone. Mean daily doses were buspirone, 20 mg; diazepam, 20 mg; and clorazepate, 24 mg. Sedation, lethargy, and depression were significantly less with buspirone than with diazepam or clorazepate and were comparable to placebo. There was no indication that other types of side effects would differ significantly from those seen with the benzodiazepines. Nervousness, headache, and dizziness were experienced more frequently with buspirone than with placebo.

Drug interactions in controlled clinical trials

As much information as possible should be obtained in clinical trials to assess possible interactions between test drugs and concomitant medications prescribed for other medical indications. Side effect profiles were compared in patients taking buspirone, mean = 20 mg/day; diazepam, 20 mg/day; clorazepate, 23 mg/day; and placebo, with or without concomitant medications. Approximately 1,000 anxious patients were included in the analysis; 700 received buspirone. The use of a variety of common medications did not affect the side effect profile in the buspirone, clorazepate, and placebo groups, but did increase the incidence of side effects in the diazepam group. The increased incidence of sedation noted with diazepam and clorazepate, however, was not due to concomitant medication.

Value of a single night-time dose of potassium clorazepate in anxiety: a controlled trial comparison with diazepam

A total of 29 patients with anxiety or anxiety/hysteria, participated in a double-blind, cross-over trial of two benzodiazepine anxiolytics, diazepam and potassium clorazepate. The problems of a 'carry-over' effect and a possible order of drug administration effect are discussed in relation to analysis of results. Clorazepate proved the more effective drug, as shown by a reduction in total symptom scale of Kellner Symptom Rating Test and the reduction in sub-scales for anxiety, depression, somatic complaints and general neurotic symptoms with parallel symptom reduction in linear analogue scales. Side effects were infrequent with both drugs and posed no clinical problem. Potassium clorazepate in a single nightly dose of 15 mg proved to be more effective than thrice daily (5 mg) diazepam.

[Mnemic disturbances following experimental alcohol-tranquilizer application (author's transl)]

Mnemic disturbances occurred in 8 of 14 subjects during a pharmcopsychological investigation of possible interactions between alcohol and dipotassium chlorazepate (Tranxilium). The blood alcohol concentrations were between 0.87% and 1.32%; the serum concentrations of the active metabolite nordiazepam were in the therapeutic range between 145 ng/ml and 345 ng/ml. The constitutional, dispositional, and situative conditions are presented. The forensic medical interpretation of such mnemic disturbances must be made critically and with reservation when evaluating a psychopathological state.

Potassium clorazepate (Tranxene)-induced jaundice

A first report of jaundice and hepatic necrosis probably due to potassium clorazepate is described. The histology is discussed and it is suggested that the drug should not be given in the presence of suspected hepatic dysfunction.

Evaluation of clorazepate (Tranxene) as an anticonvulsant--a pilot study

Desmethyldiazepam--providing the long-term anticonvulsant effect when diazepam is given orally--is conveniently administered as clorazepate (Tranxene). In this study, clorazepate was compared to phenobarbital as a secondary anticonvulsant in eight ambulatory, adult outpatients. Stable doses of phenytoin were maintained throughout. Drowsiness was present in all on phenobarbital, but there were no clorazepate-related side effects. Seizure control did not differ for each treatment. Addition of common side effects of phenytoin and phenobarbital limited the attained serum levels of each when used together. Clorazepate doses in the 0.56-mg-per-kilogram range gave desmethyldiazepam levels in the 1.0-microgram-per-milliliter range. Induction of metabolism was suggested by falling desmethyldiazepam levels despite increasing doses. Clorazepate is an effective, nontoxic secondary anticonvulsant.

Single daily dose treatment of anxiety with clobazam or dipotassium clorazepate

1 Forty-four clinically anxious patients entered a comparative double-blind trial of clobazam 20 mg, clobazam 30 mg and dipotassium clorazepate 15 mg, all drugs given as a single dose at night. 2 Assessment by the Hamilton Anxiety Scale, Morbid Anxiety Inventory (Salkind) and a Visual Analogue Scale showed a statistically significant improvement for all treatment groups after 2 weeks, with continued improvement after a further 2 weeks. 3 Daytime drowsiness was the commonest side-effect in all treatment groups but there was a tendency for a lower incidence in patients on clobazam. There was no evidence of a dose-related incidence of drowsiness in the clobazam 20 mg and 30 mg groups. Other side-effects were few and nonspecific. 4 Clobazam is a 1,5-benzodiazepine with an elimination half-life of 18 hours. When given in single doses of 20-30 mg at night it has an equivalent effect to dipotassium clorazepate 15 mg.

Clorazepate: double blind crossover comparison of a single nightly dose with diazepam thrice daily in anxiety

In a double blind cross-over study in 40 patients with mild to moderate anxiety, clorazepate 15 mg at bedtime was as effective as diazepam on global rating and slightly superior on target symptom assessment. There was a significantly higher incidence and frequency of side effects during diazepam treatment. Occurrence of side effect related to plasma diazepam, and anxiolytic effect related to plasma nordiazepam. These results are discussed in relation to convenience of the single dose regimen and psychomotor performance.