In the postoperative period; pain, nausea, and vomiting are undesirable side effects that reduce the patient's comfort and may lead to various complications. Ondansetron is frequently used as an antiemetic and tramadol hydrochloride is used for postoperative analgesia in laparoscopic cholecystectomy. However, some studies have reported that there is a drug interaction between these two drugs and they reduce each other's effects, thus requiring more analgesics in the postoperative period.

The aim of this study is; To evaluate whether ondansetron reduces the analgesic efficacy of tramadol hydrochloride in laparoscopic cholecystectomies.

During the operation, 4 mg iv ondansetron (2mL) will be administered to the ondansetron group and 2mL iv 09% saline will be administered to the placebo group. The patients' heart rate, blood pressure, oxygen saturation, sedation score (with Ramsey Seading Score), amount of pain (with NRS), degree of nausea (with NRS), whether there is vomiting, whether analgesic or antiemetic treatment is required, and the amount of tramadol use will be recorded at 1, 2, 4, 8, 12 and 24 hours in the postoperative period.

Inclusion Criteria:

60 patients over the age of 18, ASA I-II, undergoing laparoscopic cholecystectomy

Exclusion Criteria:

1. Patients under 18 years of age
2. Patients with known allergies to the drugs to be used
3. Pregnant and breastfeeding mothers
4. Patients who received antiemetic or cortisone within 24 hours before surgery
5. Patients with mental illness or epilepsy
6. Patients with alcohol or substance abuse