Introduction:
Plasma that constitutes more than half of the circulating extracellular volume is of utmost importance in sustaining life. But the fact to be understood here is that even such a vital component has got ironical characteristics of its own. These are undeniably true in case of peptides in the blood which culminates both peptides and peptidases side by side. This we mean for the kinins in plasma which are ubiquitous throughout with kininases alongside. Even though their absolute roles are yet to be established their definitive roles are brought to light by the extensive research which is being done today. This has become an area of interest in the recent years in the fields of physiology, pharmacology, pathology and therapeutics. This review narrates about the kinins commencing from their discovery to their physiological roles and its implications in drug development, and tries to analyse the most noted part which is the failures that overshadows the drug development in case of kinins.