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Updated: Oct 23, 2026
Basophil Activation Test for Allergy Diagnosis
Published on: May 31, 2021
H1- and H2-receptor antagonists prevent histamine release in allergic patients after the administration of
1Department of Dental Anesthesiology, Faculty of Dentistry, Kyushu University, Fukuoka, Japan. kimura@dent.kyushu-u.ac.jp
Objective:
The prophylactic effects of H1- and H2-receptor antagonist against histamine release and clinical symptoms (e.g. skin reactions, hemodynamic changes) were examined in 80 allergic patients after the administration of midazolam-ketamine.
Subject:
We examined 80 allergic patients undergoing oral surgery.
Methods:
A prospective randomized controlled study was performed in four groups of 20 patients who received either hydroxyzine (H1-receptor antagonist), chlorpheniramine (H1-receptor antagonist), a combination of chlorpheniramine and famotidine (H1- and H2-receptor antagonist) or a placebo (control) as premedications. Venous blood samples were obtained before introduction as a control and 0.5, 1, 3, 5 min after the administration of midazolam-ketamine in order to measure the plasma histamine level. In addition, any observed hemodynamic changes were simultaneously recorded. The plasma histamine level was measured using the HPLC (high performance liquid chromatography) post-label system.
Results:
The patients who were treated with both chlorpheniramine and famotidine demonstrated a high level of basal plasma histamine compared to the patients who were treated by hydroxyzine alone (p < 0.05), and they also showed less histamine release and anaphylactoid reactions during midazolam-ketamine anesthesia. Allergic patients demonstrated a high percentage of eosinophils, with an average of 4.79 +/- 3.78%.
Conclusion:
The administration of midazolam-ketamine in allergic patients demonstrated no significant problems. The combined premedication with chlorpheniramine and famotidine was thus found to have the most prophylactic effect against histamine release after the administration of midazolam-ketamine in allergic patients in spite of a high level of basal plasma histamine.
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