Epinephrine is an adrenal hormone and a neurotransmitter found in vertibrates and protozoans. They are also produced at the ends of sympathetic neurons as chemical mediators for conveying the nerve impulses to effector organs. Epinephrine come under a group of monoamines called the catecholamines. It is produced in neurons of the central nervous system and in the chromaffin cells of the adrenal medulla from the amino acids phenylalanine and tyrosine.