Effect of Meperidine on Equine Blood Histamine, Tryptase, and Immunoglobulin-E Concentrations

Abstract

Objectives: To evaluate changes in immunological parameters following subcutaneous (SC) and intramuscular (IM) administration of meperidine in horses through quantitative analysis of plasma tryptase, histamine, and IgE levels.Methods: Six adult horses were enrolled in a prospective randomized crossover design. Horses were administered one treatment per day, with a seven day washout period: (a) meperidine 1 mg/kg IM, saline 6 mL SC; (b) saline 6 mL IM, meperidine 1 mg/kg SC; (c) saline 6 mL SC, saline 6 mL IM. Blood samples were obtained for plasmatic histamine (baseline, 5, 10, 15, 30, and 60 min) via LC-MS/MS and plasmatic tryptase (baseline, 15, 30, 60, 120, and 240 min) quantification with enzyme-linked immunoabsorbent assays. Serum immunoglobulin E (IgE) concentrations prior to any meperidine treatment and 7–14 days following the first meperidine treatment were evaluated with enzyme-linked immunoabsorbent assays. Histamine and tryptase concentrations were evaluated with a mixed-effect analysis of variance. The levels of IgE at baseline (before the administration of the first dose of meperidine) were compared with the IgE values at 60 min following the second meperidine administration with the Paired t test. Biopsies of localized injection site reactions from subcutaneous meperidine administration were collected from two horses.Results: No statistically significant elevations from baseline in histamine (p = 0.595), tryptase (p = 0.836), or IgE (p = 0.844) were found in any of the horses in this study. There were no differences between treatment groups. Administration of SC meperidine caused a localized vasculitis and thrombosis with regional edema and hemorrhage.Conclusion: No evidence of anaphylactoid or anaphylactic type reactions occurred following IM or SC meperidine administration.

A preliminary study comparing the sedative, cardiorespiratory, and histaminic-releasing effects of intramuscular and intravenous administration of pethidine (meperidine) with midazolam in healthy cats

“…Trenholme et al. ( Trenholme et al., 2020 ) showed that IM or subcutaneous administration of pethidine did not induce histamine release, whereas a clinical case report from Clutton ( Clutton, 1987 ) strongly suspected that histaminic effects led to hypotension and tachycardia in two horses.…”

“…In a recent equine study, specific focus was placed on blood parameter level changes associated with pethidine injection. Subcutaneous and intramuscular (IM) administration of pethidine did not induce a statistically significant increase in concentration of histamine, tryptase, or IgE compared to the baseline values ( Trenholme et al., 2020 ). However, in all horses, subcutaneous pethidine injection caused localized vasculitis and thrombosis with regional edema and hemorrhage ( Trenholme et al., 2020 ).…”