Electroencephalographical analysis of acute drug intoxication--SS Bron solution-W.

Disturbances of the central nervous system due to abuse of SS Bron solution-W (B-solution), an antitussive and expectorant containing dihydrocodeine and other constituents, were studied in rabbits. Animals were given 20 ml/kg of B-solution orally at 4 hour intervals for 8 hours or more, and changes in the electroencephalograms (EEGs) from the reticular formation(RF), hippocampus(Hpc) and sensorimotor cortex(Cm) were examined. The following results were obtained. About 3 hours after administration of B-solution, the EEG from the Hpc showed low voltage, slow wave, the heart rate decreased rapidly, and the respiratory rate increased. After about 7 to 7.5 hours, the EEG from the Cm showed slow wave hypersynchrony and stimulation of the RF with square pulses of 2.0 V induced slight arousal reactions in the Cm and Hpc. The blood pressure and respiratory rate decreased, and ECG changes indicated atrial flutter-fibrillation and ventricular tachycardia. Power-spectrum array analysis indicated increase of slow frequency discharges in the EEGs from all regions. The slow wave hypersynchrony of the EEG from the Cm and slow wave, low voltage of the EEG from the Hpc seemed to be associated with hallucination and delusion.