Asthma is defined as a complex allergic disease of respiratory system which is characterized by
airway inflammation & bronchial hyper-responsiveness to many allergens and due to interaction of many
components of immunity system & resident lung cells. Asthma is currently a worldwide problem with around
300 million people around the globe suffering from it and about 250 thousand deaths are reported annually.
Asthma remains an area of considerable unmet medical need. Few new drugs have made it to the clinic during
the past 50 years, with many that perform well in preclinical animal models of asthma, failing in humans
owing to lack of safety and efficacy. The utility of in vivo studies and demand for more predictive models and
tools are based on the latest technologies. Studies have been conducted with in vitro and in vivo models but
disease mechanism are still unclear. At present, there are no standardized experimental protocol models for
asthma, most laboratories have developed and adopted own protocol with little modification. In this article,
we discuss various in vivo, in vitro models of asthma which may describe the various mechanisms & pathophysiology
involved in allergic and inflammatory disease & also provide investigation of new therapeutic
substances for allergic disorders.