Background: Antibiotic treatment is a double-edged sword that alters the natural balance of organisms. Each time an antibiotic is used to eliminate bacteria, other pathogens gain strength. The circulation within the pulp is compromised in the presence of inflammation or infection. Because an antibiotic is carried by the vascular system, its ability to reach bacteria in a therapeutic concentration will be limited. This environment diminishes the efficacy of the antibiotic. The aim of this study was to evaluate the role of antibiotics in patients with irreversible pulpitis. Materials & methods: Patients were divided into two groups. First group- endodontic treatment with antibiotic-analgesic regimen. Second group- endodontic treatment without antibiotic analgesic regimen. The results were subjected to statistical analysis. Results: No significant differences were obtained between two groups. Conclusion: An infection must either be persistent or systemic to justify the need for antibiotics. Pain alone or localized swelling donot require antibiotic treatment. Although the incidence of bacteremia is low with root canal procedures, antibiotics may be recommended prophylactically for some medically compromised patients.