Background: Unilateral block shows advantages of spinal block without the typical adverse effects seen with bilateral block. In this study, we compared unilateral spinal anaesthesia using isobaric levobupivacaine admixed with fentanyl or clonidine in patients undergoing varicose vein surgery in terms of onset, duration of motor and sensory block, hemodynamic parameters, requirement of first analgesic rescue therapy and side effects. Material and method: 90 patients of ASA I/II scheduled for varicose vein surgery allocated into three groups (n=30). All three groups received 5mg isobaric levobupivacaine + normal saline(0.5ml) group A, 5mg isobaric levobupivacaine+25 µg fentanyl(0.5ml),group B, 5mg isobaric levobupivacaine+ 25 µg clonidine (0.5ml ),group C making volume of 1.5 ml in each respectively for unilateral spinal anaesthesia. Results: All groups were comparable with respect to age, height, weight and ASA. Sensory block onset time was faster in group B(3.20±1.00 min) as compared to group A and C while onset of motor block was earlier in group C(10±0 min). Duration of sensory and motor block and requirement of rescue analgesia was prolonged in group C(5.15± 0.60) as compared to group A and B. All hemodynamic parameters were stable with no intra and postoperative complications. Conclusion: Major advantages of unilateral spinal anaesthesia are its hemodynamic stability, increased patient autonomy, early discharge and no complications as seen with conventional bilateral spinal block so this might be a better alternative for outpatient procedures.