Snakes have fascinated the imaginations of people since the dawn of civilization. Their deadly venoms cause significant mortality and morbidity worldwide, and strike fear in most of us. Snake venoms contain a huge variety of molecules affecting vital physiological systems, and scientists are turning some of these life-threatening toxins into a source of life-saving therapeutics. Since the approval of captopril--the first drug based on snake venom protein--more than 30 years ago, snake venom toxins have become a valuable natural pharmacopeia of bioactive molecules that provide lead compounds for the development of new drugs. Many toxins are being explored and developed into drugs for the treatment of conditions such as hypertension, thrombosis and cancer. A number of new drugs are constantly emerging from this pipeline. In this review, we briefly highlight the molecular basis of developing therapeutic agents, such as Captopril, Tirofiban, and Eptifibatide, from snake venom proteins. We also discuss the successes and failures as an update to the advances in the field.