In this study, the combined use of α2-adrenergic receptor agonists and calcium channel blocker, nicardipine as a vasodilator revealed the following. Nicardipine attenuated the cardiovascular adverse effects of medetomidine and medetomidine-midazolam, and to enhance the antagonistic effect and changes in hemodynamics of atipamezole in dogs. The use of medetomidine-midazolam-nicardipine combinations can be performed on dynamic hepatic computed tomography in the same imaging phases as conventional isoflurane anesthesia in dogs. The effects of constant rate infusion of nicardipine attenuated the cardiovascular adverse effects of dexmedetomidine in dogs under sevoflurane-dexmedetomidine anesthesia without affecting the minimum alveolar concentration of sevoflurane.