Gamage is veteran social welfare personnel in Sri Lanka and a reputed public servant with over 34 years of experience. He is known both locally and regionally as an expert in the fight against drugs and illegal substances.
He is the former Director General of National Dangerous Drugs Control Board with over 34 years of experience. He also worked as the Commissioner of the ICCE (International Center for Credentialing and Education of Addiction Professionals) with the Colombo Plan and as the Executive Director of International Institute of Addiction Management. Gamage currently serves as the Academic Registrar of the Colombo School of Business and Management.
He has also been actively involved in planning and implementing WIF-WACC project where he contributed towards the village and community development through communication in Mineripitiya in Ratnapura District & UNIFEM women's Development Project in Weerambuwa & CIDA , ICon Project for Fisheries women's Development Project in Pelana and Talramba in Matara District and Bassiyawatte and Talahena in Gampaha District & Unicef, USAID, HEB Projects on training for Health workers on basic communication in six districts, Kalutara, Kegalle, Ratnapura, NuwaraEliya, Kurunegala and Puttalam.
He has also conducted many speeches, lectures and chaired many forums on communication and community development for Government and Non-governmental organizations with the aim of creating awareness non Drug abuse, women development and community development and if quantified they include, 3000 educational lectures on drugs prevention and control, trained 10,000 professionals on drug abuse prevention and enforcement, established over 300 drug prevention societies island-wide, produced over 500, 30 minutes radio programmes and broadcasted over SLBC and Lakhanda & produced 110, 30 minutes live programmes on drugs control and telecasted over ITN.
Gamage holds a Masters in Mass Communication and Post Graduate Diploma in Writership and Communication from the University of Jayawardenepura and a Bachelor of Arts from the University of Colombo. He is a veteran in the field of drug abuse and community development.