Vagus nerve stimulation (VNS) is a well-established treatment modality for patients with refractory seizures. The optimal output current is individually determined by evaluating patient tolerance or reaching seizure control. VNS is currently also investigated as a potential treatment for epilepsy in dogs. In one study the optimal output current in dogs with refractory epilepsy was determined to be the highest current that did not elicit coughing. Ten Beagle dogs were implanted with a Cyberonics® pulse generator and helical electrodes around the left vagosympathetic trunk. One dog developed a left-sided Horner syndrome and was excluded. Starting 4 weeks after implantation, the optimal output current was assessed on a weekly basis for 6 weeks by stimulating the vagal nerve during 2 minutes with intermittent pulse trains (500 ms, 30 Hz, 7s on, 0.3 min off). The initial stimulation intensity was set at 0.125mA and this output current was gradually increased in steps of 0.125mA until coughing was observed (coughing threshold). The optimal current was defined as 0.125mA below the coughing threshold. During the ramping-up procedure laryngeal vibrations could be palpated 0–0.5mA beneath the coughing threshold. Overall, the optimal output current was stable over time (7 dogs). At 4 weeks after implantation the optimal output current ranged between 0.125 and 1.5mA (mean±SD=0.722±0.384mA). At 10 weeks after implantation the optimal current ranged between 0.375 mA and 1 mA (mean±SD=0.611±0.202 mA). In 3 out of 7 dogs a small decrease of 0.125 mA between week 5 and 6 after the implantation was found. In 1 dog the current decreased from 1.5 mA to 0.625 mA and in 1 dog there was an increase from 0.125 mA to 0.375 mA. There is a wide range in optimal current values for acute VNS in dogs. Week 6 after implantation seems to be an ideal moment to assess optimal current values. Moreover, laryngeal vibrations can be palpated in dogs during VNS.