Evaluation of the sedative properties of oral trazodone, gabapentin or their combination in healthy cats.

Objectives: Sedation before veterinary visits is advocated to help reduce fear and anxiety in cats and facilitate safe handling. The aim of this study was to evaluate the effectiveness of trazodone, gabapentin and a trazodone/gabapentin combination for oral sedation in healthy feline patients before blood donation.

Methods: A total of 21 cats were included in the study. Baseline sedation scores were obtained, and cats were randomly assigned to receive oral trazodone at 5 mg/kg (T), oral gabapentin at 10 mg/kg (G), their combination (TG) or placebo (control group). A sedation score was obtained 1 h after drug administration. A blood sample was obtained at the time of blood collection for quantification of drug plasma concentrations. Agreement between observers was tested with a Cohen's Kappa test. Sign tests to compare change within treatment and a Skilling-Mack rank ANOVA to test for differences between groups were performed to compare pre- and post-sedation scores as well as a magnitude of differences over time between the groups. A Spearman's rank correlation coefficient test was used to correlate sedation scores with drug plasma concentrations.

Results: Post-sedation final scores were significantly higher only in the T (P = 0.022) and TG groups (P <0.001). The magnitude of change between pre- and post-sedation scores was larger in the TG (P <0.0032) and T groups (P <0.038) compared with the control group. There were no other significant differences between the groups. There was no correlation between drug plasma concentrations and sedation scores in any of the groups.

Conclusions and relevance: Administration of oral trazodone alone at 5 mg/kg or in combination with gabapentin at 10 mg/kg resulted in significant sedation in healthy cats with no evident side effects. The degree of sedation was more profound when both drugs were combined, but a gabapentin dose of 10 mg/kg alone failed to provide significant sedation in this population.