Hypotension following spinal anaesthesia is most commonly encountered event. Vasopressors are the most preferred drugs to treat and prevent hypotension due to spinal anaesthesia. Currently both norepinephrine and phenylephrine are the favored vasopressor to counteract spinal anaesthesia induced hypotension in obstetric population. There are not many studies comparing the effect of equipotent dose of norepinephrine and phenylephrine in treating spinal anaesthesia among elderly population. In this study we aim to compare the changes in heart rate and blood pressure following prophylactic intravenous infusions of norepinephrine or phenylephrine in elderly patients under elective surgery under spinal anaesthesia. We will recruit elderly patients above 50 years of age considering all the inclusion and exclusion criteria. In this randomized double blind study, we will obtain informed consent from the patient and after administration of spinal anaesthesia we start infusion of either norepinephrine or phenylephrine after one minute in our sample of patients and will monitor for incidence of hypotension, bradycardia, reactive hypertension and other adverse events for 45 minutes following the spinal anaesthesia procedure. Postoperatively we will monitor the patient in recovery room the next 24 hours for any adverse events. We will note the entire collected data onto study proforma and uploaded onto excel sheet. Statistical analysis will be done.