BACKGROUND: Attention deficit hyperactivity disorder (ADHD) is one of the most common childhood psychiatric disorder with a prevalence of 8-12%. Even though psychostimulants remain the treatment of choice, its cost and availability in developing countries limits the usage of the drug. In view of free availability and low cost, a Randomized controlled study was carried out using two second line drugs (clonidine and carbamazepine) in a tertiary care hospital, Pondicherry, South India. OBJECTIVE: To compare the efficacy of clonidine and carbamazepine in children with ADHD. METHOD: With approval of ethics committee, a prospective, Double-blind, Randomized controlled study of clonidine and carbamazepine was conducted with 50 children with ADHD (age group 4-12 years), over a period of 2 years (2005-07) in a tertiary care hospital, Pondicherry, South India. RESULTS: Clonidine was effective in improving the hyperactivity and impulsivity symptoms in children with ADHD as compared to carbamazepine. Statistical significant improvement was not noted with respect to inattention symptoms and other comorbid conditions. CONCLUSION: Clonidine can be a safer and cheaper alternative in treatment of children with ADHD, with a predominant effect on their hyperactivity and impulsivity symptoms.