Background: Hypotension is the commonest side effect after giving spinal anaesthesia in lower segment caesarean section (LSCS). Various drugs are being used to prevent hypotension due to spinal anaesthesia. Aim: The present study was planned to compare role of preemptive (used just after giving spinal anaesthesia) Phenylephrine and Ephedrine intramuscularly (IM) in reducing spinal anaesthesia induced hypotension and other adverse effects in LSCS. Settings and design: After approval from ethical committee (Reference No: SGRR/IEC/16/18) a prospective, double blind randomized control clinical study was conducted. Material and method: Total 90 pregnant females with single pregnancy, term gestation and aged between 18-45 years and American Society of Anaesthesiologist (ASA) class І, posted for LSCS were selected and randomly divided by using envelope technique into three groups each having 30 patients. In Group A Phenylephrine 4 mg, in Group B Ephedrine 30 mg and in Group C normal saline was given by intramuscular route. Statistical Analysis: One way ANOVA test was used to compare means of different groups whereas Chi- square test was used to compare proportions of different group. p value <0.05 was considered statistically significant. Results: Mean blood pressure values were found maximum in Phenylephrine group followed by Ephedrine group and least in control group. Incidence of hypotension and nausea/vomiting was seen least in Phenylephrine group in comparison to other groups. Conclusion: Phenylephrine and Ephedrine both were effective in maintaining mean blood pressure, lowering incidence of hypotension and associated adverse effects related to spinal anaesthesia however Phenylephrine was found more effective.