Shivering is recognized as an undesirable effect of spinal anesthesia. Patients undergoing gynecological surgeries may experience increased physiological stress due to perioperative shivering. This condition can lead to serious complications such as increased oxygen consumption, resulting in hypoxemia, lactic acidosis, and elevated carbon dioxide production. Additionally, shivering may cause increased intraocular and intracerebral pressure and can interfere with monitoring techniques like pulse oximetry, blood pressure, and electrocardiography. If not treated, shivering can negatively impact patient outcomes, prolong recovery times, and extend hospital stays. The use of opioids has shown effectiveness in treating shivering. Based on the existing literature, it is hypothesized that there is no difference in the efficacy of nalbuphine and ketamine in controlling perioperative shivering in patients undergoing gynecological surgery under spinal anesthesia. Therefore, the study aims to investigate and compare the effectiveness of nalbuphine and ketamine in managing post-spinal shivering in these patients, focusing on i) incidence of shivering, ii) severity of shivering in both groups, iii) complications such as vomiting and sedation, and iv) the need for rescue medication. Preventing and managing shivering is crucial for successful surgical outcomes. To date, no comparative study has evaluated the intravenous efficacy of these two drugs in this patient population for post-spinal shivering control. This will be a double-blind, randomized controlled trial conducted in the Anesthesiology Department at DHQ Teaching Hospital Sargodha. A total of 90 gynecological patients will be enrolled and divided equally into two groups: Group N receiving nalbuphine and Group K receiving ketamine. Parameters such as heart rate, systolic and diastolic blood pressure, temperature, oxygen saturation, incidence and grade of shivering, complications like sedation and vomiting, and the need for rescue medication will be recorded. The study may face limitations due to the lack of advanced monitoring equipment for assessing parameters like core body temperature at the study site. Evaluations of cognitive and psychomotor functions cannot be conducted due to resource constraints. The use of a non-probability convenience sampling method, while practical, may introduce bias. Additionally, precise blinding may not be achievable due to limited technical personnel, and financial constraints prevent increasing the sample size.