Difference - Drug substance over Drug product
The difference between drug substance and Drug product are as follows. Drug substance is the active ingredient or Active pharmaceutical ingredient which is used to make the drug product, It is a pure material which exerts pharmacological action on the body. While drug product is the combination of drug substance or two or more more drug substance or excipients. Tablets, capsules or injections are known as drug product while the active part which exert action on the body which is present in tablets, capsules or injections are known as drug substances.