Introduction: Anaesthesia to a parturient is not only unique but also requires highest degree of care because the anesthesiologist has to look after two individuals, the mother and foetus. Hypotension during subarachnoid block for caesarean delivery can have detrimental effects on both mother and foetus. Objectives: To determine the efficacy of Ephedrine and Mephentermine prophylactically in managing the hypotension for caesarean section under sub arachanoid block and their undesirable side effects. Materials and Methods: Patients were divided randomly into 2 groups (E group and M group) of 30 each. Patients were premedicatated with inj. Pantaprazole 40mg and inj. Metoclopramide 10 mg and pre loaded with ringer’s lactate at 10ml/kg infusion in the morning of the day of surgery. Baseline pulse rate, blood pressure, and SpO2 were recorded. Subarachnoid block was performed in sitting position, under aseptic conditions with a hyperbaric Bupivacaine 0.5%, 2cc (10mg) using 25 gauge Quincke’s needle. Group E received Ephedrine 3mg and Group M received Mephentramine 3mg prophylacticaly immediately after subarachnoid block.Blood pressure and pulse rate were measured every minute until the delivery, then every 5 minutes till the end of surgery. APGAR score were noted to assess the fetal outcome. Patient were monitored for 2 hours in the post operative recovery room soon after surgery for any untoward complications. Results: Mephentermine significantly increases the systolic blood pressure, mean arterial pressure and reduces the heart rate compared to Ephedrine. Conclusion: Maintenance of SBP between ‘hypotension value’ and baseline value by carefully titrating the vasopressor results in a satisfactory fetal outcome. Both ephedrine and mephentermine are equally efficacious for the management of maternal hypotension in terms of frequency of usage and result in a similar neonatal outcome. Our results suggest that Mephentermine increases the systolic blood pressure and decreases heart rate compared to Ephedrine and therefore more potent for management of hypotension before delivery of the baby during spinal anaesthesia in patients undergoing elective Caesarean section.