OBJECTIVE: To compare recovery times from vecuronium-induced neuromuscular block with sugammadex or neostigmine, and to estimate recovery times using simulated, clinically relevant scenarios, with nonlinear mixed-effect (NLME) models. STUDY DESIGN: Randomized clinical trial and pharmacological modeling. ANIMALS: A group of 30 adult dogs of various breeds undergoing ophthalmic surgery. METHODS: Neuromuscular block was induced and maintained with vecuronium. Train-of-four (TOF) count (n) or ratio (%) was quantified with acceleromyography every minute. Dogs were randomized to intravenous injection of sugammadex (4 or 1 mg kg RESULTS: Reversal occurred at a TOF count or ratio of 1 (0-8)%, 1 (0-52)% and 2 (0-30)% for sugammadex 4 mg kg CONCLUSIONS AND CLINICAL RELEVANCE: Recovery from vecuronium-induced neuromuscular block with sugammadex was dose dependent and faster than neostigmine. Substantial variation in recovery times is expected with low-dose sugammadex and neostigmine, highlighting the importance of monitoring.