Introduction: Oppositional defiant disorder (ODD) is a disruptive behavioural disorder, characterized by enduring patterns of negativistic, disobedient, and hostile behaviour toward authority figures, as well as an inability to take responsibility for mistakes, leading to placing blame on others. Children frequently argue with adults and become easily annoyed by others, leading to anger, resentment and may have difficulty in the class room. It significantly affects the mental health and increasing the risk of developing other mental health issues like depression, anxiety, and substance abuse disorders. ODD is a rising concern in paediatric mental health. There is a growing global demand for non-drug, integrative approaches that are safe, effective, and culturally acceptable. This study addresses that gap by evaluating individualized homeopathy in a clinical setting. Purpose: This study aims to investigate the behavioural changes in children and its impact on the mental health in the context of managing of the oppositional defiant disorder on complementary medicine through homeopathy medicines. Methodology: 45 children were diagnosed with Oppositional defiant disorder with the age between 5 to 15 years. Three children dropped out, resulting in a total of 42 children completing the study. Pre and Post Assessment was done using Vanderbilt Assessment Scale. Post assessment was done at 6th, 12th and 18th month. Results: Out of 42 cases, 6 (14.28%) cases with mild improvement, 22 (52.38%) cases with moderate improvement, 10 (23.80%) cases with marked improvement and 4 (9.52%) cases showed no improvement. Conclusion: Individualized homeopathic treatment has shown a positive role for the management and treatment of disruptive behavioural disorder. Further research through randomized, placebo-controlled trials is necessary to confirm efficacy and to guide clinical application more robustly. © 2025 Elsevier B.V., All rights reserved.