Background: Adverse Drug Reactions (ADR’s) to anti-TB drugs might contribute to the extension of treatment period, final termination, drug resistance and treatment failure as Anti-TB medications are the main stay treatment in Tuberculosis. These ADR’s may cause unintended interruption of treatment which may pose a challenge in TB management. Aim: This study aims to explore and observe adverse reactions of 1st line antitubercular drugs in DOTS treatment. Methodology: This is a analysis of ADRs of antitubercular drugs that were reported to ADR monitoring centre (AMC), SDSTRC and RGICD ,Bangalore either by spontaneous reporting or found by active surveillance methods. This study was for about 32 months. During this period all the ADRs caused by antitubercular drugs reported to the AMC were collected and classified based on WHO causality assessment. Later all those data were analyzed and results were generated Results: A total of 507 ADR’s were reported and out of which the majority of ADR’s were reported in adult population (45%). Based on gender, Male had a higher incidence of ADR (324, 63.9%). Based on WHO causality assessment scale, 69.4% of ADRs were ‘possible’ followed by 25.2% being ‘probable’ and 4.1% being ‘certain’. Conclusion: Monitoring of patients on Anti tubercular treatment with early identification and appropriate management of ADR becomes very essential. The timely and aggressive management of adverse effects of anti-tubercular drugs greatly facilitates patient adherence.