After obtaining institutional ethics committee approval and written and informed consent from patients of ASA I, II or III who will be undergoing  surgery under general anaesthesia will be included in this study. Preanaesthetic check-up will be carried out in all patients.

        Patients will be kept Nil by mouth(NBM) for 8 hours for solids and 2 hrs for clear liquid  before surgery.Appropriate fluids will be started in preoperative room and will be continued in the operation theatre (OT). After the patient is taken in the operating room, monitors like Pulse oximetry, electrocardiogram, non invasive blood pressure monitoring, manual blood pressure monitoring and end tidal carbon dioxide monitoring device will be applied and hemodynamic variables will be measured on arrival to the OT and every 5 min thereafter till the end of surgery.

       Standard anesthesia technique  for induction of general anesthesia will be used. Patients will be premedicated with injection midazolam, fentanyl, xylocard as per protocol and  intravenous amisulpride 5 mg will be given. Patients will be induced with propofol and with or without  muscle relaxation as per the case.  General anaesthesia will be given by Endotracheal Tube/ IGEL/ LMA. Anesthesia will be maintained by O2,AIR and Sevoflurane/ Desflurane. End-tidal CO2 will be maintained between 35 and 40 mm of Hg. Pulse rate, electrocardiogram, NIBP, and oxygen saturation will be  monitored continuously throughout the procedure. At the end of procedure if the patient will be given non depolarizing muscle relaxant neuromuscular blockade will be reversed with Inj.neostigmine and Inj.glycopyrolate. Before  extubation as per the standard protocol Inj paracetamol 1gm(100ml)will be given.After extubation, patients will be shifted to recovery room for further observation.Post operative period will be defined from the closure of wound till 24 hours.

       In the post-operative period, incidence of nausea, vomiting will be assessed by direct questioning  the patient at 0.5, 1, 2,  6, 12, 24 hours after surgery.Severity of nausea will be assessed using a 11 point verbal rating scale(VRS), with 0 representing no nausea at all and 10 the worst nausea imaginable and “significant nausea” will be defined as any score of 4 and over.

      The incidence of PONV will be defined as the occurrence of nausea and vomiting in the 24 hour period after the end of the surgery and time of the incidence of PONV from the administration of amisulpride will be noted.If it occurs, then rescue antiemetic ondansetron 4 mg intravenous will be given and  total frequency of rescue anti-emetic doses given in the 24 hour postoperative period  will be observed with time.

       Type of rescue analgesic given in the first 24 hours will be noted.