With over 15 years experience conducting research, Dr. Weerasinghe has been Principal Investigator or Sub-Investigator on more than 400 clinical research studies. He is board-certified in Internal Medicine and has extensive practice experience in managed care settings. He was the Medical Director of an HMO for eight years, the Medical Director of a hospital for seven years and the Medical Director of a multi-specialty group practice for 10 years. He has served as Principal Investigator or Sub-Investigator in the areas of hypertension, diabetes, obesity, hyperlipidemia, asthma, osteoarthritis, hormone replacement therapy, smoking cessation, peptic ulcer disease and contraception.