What is considered one of the main methods of drug classification?

Chemical make-up is indeed one of the main methods of drug classification. This method categorizes drugs based on their chemical structure and the specific elements and functional groups they contain. Understanding a drug's chemical make-up can provide crucial insights into its effects on the human body, metabolism, and potential interactions with other substances. This classification is fundamental in pharmacology as it helps healthcare professionals to predict how a drug behaves in the body, thereby aiding in the development of effective therapeutic strategies.

Other methods, such as effects and legal definition, also play important roles in drug classification but are not as universally foundational as chemical make-up. The effects method classifies drugs based on their physiological responses, while the legal definition pertains to how drugs are regulated and classified within different legal frameworks. Each of these classifications can provide valuable information, but chemical make-up is essential for understanding the inherent properties of the drug itself.