PubMed1983
In a double-blind study the clinical symptomatology and quantitatively analyzed EEG of 42 hospitalized chronic alcoholics (ICD 303) undergoing alcohol withdrawal were investigated before, during and after 3 weeks' treatment with 2 pharmacokinetically different benzodiazepines: the short-acting lopirazepam (a new pyridodiazepine) and the long-acting prazepam. At the end of weeks 1 and 3 the titrated optimal daily doses were 24 and 23 mg lopirazepam and 35 and 32 prazepam, respectively, thus confirming our earlier pharmaco-EEG predictions that on a mg to mg basis the former drug is slightly more CNS potent than the latter. Thereafter, the patient population was divided into 6 subgroups: 2 groups continuing on active medication, 2 groups receiving placebo, and 2 groups with no pharmacotherapy for 1 week. Clinical assessments included the CGI, the Hamilton Anxiety Score, the Zung Self-Rating Scale for Anxiety and Depression, the Zerssen Befindlichkeitsskala and the questionnaire for somatic findings and side effect and were carried out on days 0, 7, 21 and 28 as was a radioreceptor assay for benzodiazepines in plasma. Quantitative EEG investigations were carried out on days 0, 21 and 28 and included recordings before and 2 h after one single dose of 10 mg. Statistical analysis demonstrated a marked and highly significant decrease in psychopathology as well as good drug tolerance at the end of the first week of therapy and thereafter a slight continuation in improvement until the end of the 3rd week. There were, however, no statistically significant differences between the 2 active compounds, nor were there any statistically significant differences between the 6 subgroups in the 4th week. On the other hand, blood level investigations demonstrated that even after a 3-week treatment period, blood levels dropped down to a morning minimum 12 h after the last evening medication of the short-acting lopirazepam, while plasma levels of the long-acting prazepam remained high. This was also reflected in the spectral analyzed EEG, which showed, after one single dosage of both drugs, a typical anxiolytic profile which was more pronounced after lopirazepam than prazepam, while after the chronic administration (12 h after the evening medication) only prazepam showed an anxiolytic profile. The lopirazepam-treated patients exhibited on the one hand a lack of benzodiazepine-specific alterations, but showed on the other hand EEG changes possibly reflecting clinical improvement. The relevance of the findings will be discussed.