Clinical and experimental comparison of diazepam, chlorazepate and placebo.

A double blind clinical evaluation of chlorazepate (dipotassium-7-chloro-5-phenyl-2,2-dihydroxy-3-carboxy-1,2-dihydro-2H-1,4-benzodiazepine), diazepam and placebo on a patient group of young students, mean age 25 years, is reported. Both drugs were significantly better than placebo and according to global assessment chlorazepate was superior to diazepam. An analysis of the main target symptom revealed better effects of chlorazepate on the following items: anxiety, feeling of muscular tension and gastro-intestinal disturbances. With respect to irritability and sleep disturbances both drugs were found to be equally effective. In patients' self-ratings chlorazepate was considered superior to diazepam in giving more alertness and less drowsiness during day time. The results are discussed with reference to EEG-studies and pharmaco-kinetic properties of chlorazepate and diazepam. Performance tests in simulated car-driving by healthy volunteers did not demonstrate any significant difference as compared with placebo. The psychophysiological eeffects, however, are more pronounced after diazepam than after chlorazepate medication.