Plasma histamine levels during induction of anesthesia with propofol in dogs.

We examined a property of emulsion formation of propofol (ICI 35868) to release histamine into circulating plasma in dogs. Plasma histamine was measured with radioimmunoassay before (baseline), and 1, 5 and 10 min after the administration of 15 mg.kg(-1) propofol. There were no significant differences between the plasma histamine levels at 1, 5 and 10 min after the administration of propofol and the baseline level. We conclude that the emulsion formation of propofol of 15 mg.kg(-1) does not release histamine during induction of anesthesia in dogs.