Adrenaline is a sympathomimetic amine, alpha-and beta-adrenoreceptor agonist, synthesized from tyrosine in the adrenal medulla and released along with small quantities of nor-it into blood stream, upon stimulation by the central nervous system in response to stress, anger or fear, acting to increase heart rate, blood pressure, cardiac output and carbohydrate metabolism. Adrenaline is a very potent vasoconstrictor and cardiac stimualnt. It also acts as a bronchodialator (dilates the bronchi i.e. air passage) and relieves respiratory discomfort in bronchial asthma and emphysema.