[Premedication with H1- and H2-receptor antagonists for intravenous urography using contrast media]

Intravenous urography using Telebrix was performed on 500 patients. Two hundred patients (group I) received no pre-medication; 300 patients (group II) were premedicated with H1 and H2 receptor antagonists. All patients were examined for signs of contrast reactions, blood pressure, pulse rate and plasma histamine levels. These were measured before and three minutes after the administration of the antihistamine substances and/or the contrast medium, and also at the end of the examination. Following the administration of H1 and H2 receptor antagonists, a slight, transient and insignificant rise in plasma histamine could be demonstrated. Both groups showed a significant rise in plasma histamine levels after the injection of the contrast medium. Although the pre-medicated group contained a higher percentage of high risk patients, there were significantly fewer patients with contrast reactions. Pre-medication with H1 and H2 receptor antagonists in high risk patients is therefore advisable.