The science which deals with the drug and their action on human body is called?

The science that deals with drugs and their actions on the human body is called pharmacology. Pharmacology encompasses the study of the origins, chemical properties, biological effects, and therapeutic uses of drugs. It is a broad field that includes understanding the mechanisms of drug action, the side effects, the potential interactions with other substances, and the use of drugs as medications for the treatment and prevention of diseases. Pharmacology is often divided into two main areas:

Pharmacodynamics: This area focuses on the biological and physiological effects of drugs and their mechanisms of action at the organ/system and cellular levels.

Pharmacokinetics: This area examines how the body absorbs, distributes, metabolizes, and excretes drugs, essentially what the body does to the drug over time.