Comparison of the convulsant effects of cocaine and pseudococaine in the rhesus monkey

The convulsant effects of cocaine and its C2-epimer, pseudococaine on EEG, respiration, heart rate and behavior were studied in the rhesus monkeys with electrodes implanted in the brain. Intravenous injections of cocaine (3.0 to 8.0 mg/kg) and pseudococaine (3.0 to 7.0 mg/kg) in the animals produced a similar pattern of clonic convulsions accompanied by marked increases in the heart and respiratory rates with mydriasis and excessive salivation. However, both isomers showed different effects on the EEG and animal's behavior following convulsions; e.g., the cocaine-induced convulsions were followed by low-voltage fast waves in the EEGs associated with behavioral hyperexcitation, while pseudococaine-induced convulsions were followed by high-voltage slow waves associated with behavioral depression and drowsiness with intermittent sleep. Pseudococaine was more potent than cocaine in producing convulsions in the same monkeys. The durations of convulsions produced by these drugs were dose-dependent.