Comparison of Sympathetic Blocking Drugs in Prevention of Lethal Effects of Endotoxin.

Summary and conclusions The prophylactic and therapeutic effects of phenoxybenzamine, chlorpromazine, and phentolamine against the lethal effects of Escherichia coli endotoxin in mice were compared. Mortality was observed at 24 hours and 7 days to clarify the value of these agents for “long-term” protection. Phenoxybenzamine, which has been recommended for therapy in clinical cases of bacterial shock, appears to be effective for prophylaxis but has no proven value for treatment in experimental animals. The beneficial effects of chlorpromazine are such that they delay rather than prevent the fatal reaction to bacterial endotoxin. However, the more lasting effectiveness of phentolamine in the treatment of reaction to endotoxin deserves further intensive study.