Definition:
In the biomedical industry, the active ingredient of a drug is the chemical (or biochemical) constituent that performs the intended chemistry or biochemistry in the body, inducing the therapeutic response.
Drug formulations often contain the active ingredient mixed with a carrier, coatings for easier injestion, and timed or targeted release, and even flavors and colors to make "swallowing your medicine" more pleasant. Different types of nanoparticles are being used to encapsulate the active ingredients of drugs, to reduce required doses and improve organ and tissue specificity.