Background and Aims:Breast cancer surgery can be carried out as day-care procedure to increase patient turnover, decrease disease progression and financial burden. The present study was carried out to assess the role of dexmedetomidine in breast cancer surgery as a day-care procedure.Methods:This prospective randomised, double-blind study was carried out on 100 patients screened for day-care breast cancer surgery. They were divided into two groups of 50 each; who received either normal saline (Group NS) or 0.6 μg/kg/h dexmedetomidine (Group D) infusion from 10 min before induction until skin closure. All patients were given general anaesthesia. The incidence of discharge, post-operative pain (POP), average rescue analgesia (fentanyl) required and side effects were noted. Statistical analysis was performed using Student's t-test and Chi-square test.Results:Incidence of discharge in group NS was 60% compared to 88% in Group D (P = 0.001). Average rescue analgesia requirement by group NS was 136.07 ± 43.06 μg, whereas it was 77.5 ± 29.86 μg in Group D (P = 0.01). The incidence of POP in 6 h and within 2 h of expected discharge time in Group NS was 56% and 28%, respectively, and in Group D, it was 8% in both the periods (P < 0.001 and 0.01). Side effects such as post-operative nausea, vomiting and bleeding were encountered in eight and two patients, respectively, in Group NS and two and one patients, respectively, in Group D.Conclusion:Dexmedetomidine as an anaesthetic adjuvant makes breast cancer surgery feasible on day-care basis.