Basophil histamine release in atopic patients after in vitro provocation with thiopental, Diprivan and chlormethiazole.

The degree of histamine release induced by three different anesthetic drugs was studied in vitro using basophil leukocytes from atopic patients (n = 11) and controls (n = 14). In all, eight dilutions (1/2 to 10(-5)) of Diprivan and its solvent Intralipid, thiopental and chlormethiazole in aqueous solution, were used. Histamine was released in four controls with weak dilutions (1/2 to 10(-5)) of Diprivan (n = 2) and thiopental (n = 2). The reaction with thiopental was greater than that with Diprivan. Five of the atopic subjects released histamine with one or more drug: thiopental and Diprivan four times each, Intralipid twice, and chlormethiazole once. Histamine release was greater in these patients than in controls, and occurred with dilutions ranging from 1/2 to 10(-2), except for one case. It is concluded that atopic patients release histamine with hypnotic anesthetic drugs more easily than normal subjects. In the clinical setting, where blood concentration of the drugs studied is equivalent to a dilution of less than 10(-3), they do not release much histamine. They may be used in atopic patients if the drugs are injected slowly.