Selection among benzodiazepines for alcohol withdrawal

Double blind study on the efficacy and safety of tetrabamate and chlordiazepoxide in the treatment of the acute alcohol withdrawal syndrome

1. Efficacy and safety of tetrabamate and chlordiazepoxide in the treatment of the acute or Primary Alcohol Withdrawal Syndrome (PAWS) were assessed during a randomized double blind clinical trial, carried out on sixty male alcoholic in-patients. 2. The two drugs were administered four times a day in double dummy conditions, according to a fixed-flexible decreasing dosage schedule (six days basic regimen). 3. Drug efficacy was measured daily throughout the study period using a battery of standard instruments for collecting quantitative clinical, behavioral, psychopathological and laboratory data. Side effects were daily recorded. 4. Tetrabamate was found to be as efficient as chlordiazepoxide in reducing the intensity of the PAWS, improving sleep and vital signs rapidly and alleviating anxiety progressively. 5. Tetrabamate was found particularly beneficial for severe tremor. Psychomotor and mood scores consistently favored tetrabamate, suggesting psychoanaleptic properties of this compound (increased diurnal vigilance). 6. Side effects were minimal with tetrabamate and generally of weak intensity with chlordiazepoxide. 7. The results of this study indicate that tetrabamate may represent a new alternative drug of choice for the therapy of the acute alcohol withdrawal syndrome.

Alcoholism and epilepsy

There is a scarcity of population-based epidemiological investigations concerning the prevalence of epilepsy among alcoholics, and of alcoholism among epileptic patients. Available data seem to suggest that the prevalence of epilepsy among alcoholics is at least triple that in the general population, and that alcoholism may be more prevalent among epileptic patients than in the general population. The term "alcoholic epilepsy" has been used with varying definitions in different investigations. It is suggested that a uniform definition be adopted so as to minimize confusion when comparing data from different laboratories. Although there is general agreement that excessive alcohol intake can increase the frequency of seizures in epileptic patients, limited available data suggest that light to moderate social alcohol drinking may not affect seizure frequency. However, epileptic patients should be warned about the possible adverse effects of alcohol, especially those who have refractory forms of epilepsy. Except for a few anomalous cases, evidence for the direct seizure-provoking effect of alcohol is not strong. This is because it is difficult to pinpoint alcohol as the only etiology; more likely, alcohol is only one factor among others (e.g., head trauma, cerebral infarct, alcohol withdrawal, and metabolic effects of alcohol) in provoking seizures. Because seizures are a symptom and not a disease, it is often difficult to distinguish epileptic seizures from alcohol-withdrawal seizures. Patients with only the latter kind of seizures should not need chronic antiepileptic medication.

Dissociation of tolerance and physical dependence after ethanol/chlordiazepoxide intake

The previously-observed attenuation of withdrawal reactions in mice (group B) fed an ethanol diet containing chlordiazepoxide (CDP) was not due to a difference in the rate of disappearance of blood ethanol levels during chronic diet treatment in group B compared to mice which received only the ethanol diet (group A). Injection of group A mice with CDP or N-demethyl CDP (10 mg/kg) at the time of diet withdrawal did not result in any significant attenuation of withdrawal scores. Injection of the lactam metabolite of CDP (LCDP; 10 mg/kg) resulted in significantly attenuated withdrawal scores at 4 and 6 hr only, but the pattern of withdrawal scores were different from that for group B mice. Moreover, blood LCDP level, in mice injected with LCDP, at 4 hr was at least five times higher than that attained in group B mice (from diet containing CDP). These results support our previous conclusion that the presence of major metabolites of CDP during withdrawal could only account for a minor contribution to the protective effect. Mice in A and B did not differ in the degree of functional tolerance which developed as a result of ethanol intake. Thus, there was an apparent dissociation between tolerance and physical dependence in the mice which had consumed the CDP/ethanol diet. The magnitude of decrease of GABA levels in the cerebellum and cerebral cortex at 4 hr after withdrawal also did not differ between the two groups, suggesting the reduction in GABA levels could not be correlated with the intensity of withdrawal signs.

Alcohol withdrawal reactions after chronic intake of chlordiazepoxide and ethanol

Withdrawal reactions were compared in C57BL/6J mice, which had been fed an ethanolic liquid diet containing chloridazepoxide (CDP, 3.2 or 6.4 mg/100 ml, group B or C, respectively) with those which had been administered an ethanol diet alone (group A) for 15 days. Group A showed a significantly more pronounced decrease in rectal temperature (4 to 10 hr) and a higher withdrawal score (4 to 14 hr) than mice in groups B and C. The differences in withdrawal signs still persisted even after mice were fed an ethanol diet without CDP for one extra day before withdrawal. The presence of metabolites of CDP in the blood during withdrawal could only account for a minor contribution to the protective effect. Our data are more suggestive of an increased rate of ethanol metabolism leading to lower blood alcohol levels during diet intake period as being the major factor. However we cannot rule out the alternative possibility that CDP or its metabolites might interfere with the development of tolerance to and physical dependence on alcohol.