Background: Over the past few years, there has been an increase in interest in the topic of post-operative pain treatment. The present study was conducted to assess role of gabapentin as a pre-emptive analgesic in modified radical mastectomy. Materials & Methods: 70 female patients of carcinoma breast undergoing modified radical mastectomy under general anesthesia were divided into 2 groups of 35 each. Group I patients received tab. Gabapentin 600mg orally with sips of water 1 hour before surgery and group II did not receive any drug before surgery. Parameters such as sedation score and VAS was recorded and compared in both groups. Results: The mean age in group I was 45.2 years and in group II was 47.6 years. The mean weight in group I was 55.4 kgs and 54.1 kgs in group II. Duration of surgery was 1.5 hours in group I and 2.4 hours in group II. Duration of post- op analgesia was 5.3 hours in group I and 1.9 hours in group II. The mean sedation score in group I was 1.3 and in group II was 0.7. The VAS score in group I was 5.7 and in group II was 6.2. Common side effects were nausea/ vomiting seen in 4 in group I and 2 in group II, constipation 2 in group I and 1 in group II, urinary retention in 2 in group I and 1 in group II, headache 1 in group I and 1 in group II and pruritis 0 in group I and 1 in group II. The difference was significant (P< 0.05). Conclusion: Anticipatory tab. gabapentin prolongs postoperative analgesia in comparison to the control group. Key words: Gabapentin, analgesia, postoperative analgesia