Plasma histamine levels following atracurium.

Plasma histamine levels were determined in 41 patients, 1.5 and 4 minutes after the intravenous administration of 0.6 mg/kg of atracurium. Clinical features of histamine release were sought at the time of blood sampling. Sixteen patients had elevation of plasma histamine 2.6 (SD 1.2) ng/ml 1.5 minutes after the injection of atracurium. Plasma histamine had returned to control levels at 4 minutes. There was a poor correlation between plasma histamine levels and the clinical manifestations observed. We conclude that atracurium has a low plasma histamine release potential and that cutaneous reactions after atracurium do not always indicate that plasma histamine levels are elevated.