Background:Aim: To evaluate and compare the following factors in two groups – intrathecal dexmedetomidine and intrathecal buprenorphine as an adjuvant to 0.5% hyperbaric bupivacaine for lower abdominal surgeries and lower limb surgeries. Materials and Methods: A clinical study was undertaken to compare the effects of intrathecal Buprenorphine and dexmedetomidine as additives to 0.5 % hyperbaric bupivacaine for spinal anaesthesia. This prospective, randomized, Double blind study was conducted on 60 adult patients of ASA physical status 1 and 2 in the age group of 18 to 60 years, posted for elective lower abdominal surgeries at Osmania Medical college Hospital, Hyderabad from the period 2017 – 2020. Patients were randomly allocated into two groups namely, Group BB and Group BD of 30 each. Patients in Group BB received 60mcg of Buprenorphine with 0.5% bupivacaine 15mg intrathecally. Patients in Group BD received 5mcg of Dexmedetomidine with 0.5% bupivacaine 15mg intrathecally. After connecting monitors, the required preloading done to all patients. Subarachnoid block was carried out under aseptic precautions. Pulse rate, respiratory rate, arterial blood pressure and oxygen saturation were recorded at 0, 2, 5 minutes and thereafter every 10 minutes up to 90 minutes intraoperatively