The choice of antibiotics to be prescribed by a doctor is subjective and primarily based on his clinical skill of the operator and the years of experience of the individual in managing inflammatory conditions using medications. Doctors also have a selection bias while prescribing certain medications which they are more comfortable towards and prescribe routinely. The aim of this study was to assess the antibiotics prescribed by the students as an adjunct to periodontal therapy. The current retrospective study was performed as a single centered university based design. Patient records from the Department of Periodontology, Saveetha Dental College and Hospitals, Chennai were assessed. The data retrieved were tabulated and analysed using SPSS. A total of 2120 cases were prescribed Amoxicillin, 22 cases Amoxicillin LB, 229 cases Amoxicillin and Flagyl, 27 cases Amoxicillin LB and Flagyl, 189 cases Amoxicillin and clavulanic acid and 12 cases were prescribed Doxycycline. In this study, we observed that Amoxicillin 500mg was the most prescribed medication among both surgical and non-surgical periodontal therapy thrice daily for a course of three days. Among all the drugs used in non surgical and surgical periodontal therapy the most commonly prescribed ones include Amoxicillin (88.7%) followed by Amoxicillin with Metronidazole(4.06%) and Amoxicillin combined with Clavulanic acid (4.6).