Modern pharmacology and toxicology is a branch of medicine, biology, and the pharmaceutical sciences that studies how drugs and medicines work. A drug can be any molecule, whether it’s made in a lab, found in nature, or made by the body itself. To describe any species, either endogenous or foreign, that influences the biochemistry or physiology of a cell, tissue, organ, or organism, the term “pharmacon is occasionally used. The study of interactions between living things and substances that influence both normal and aberrant biochemical activity is what it is known as in more particular terms. Pharmaceuticals are any compounds that may be used to treat or prevent disease. Toxicology is a field that draws from many other scientific disciplines, hence the work and interests of toxicologists span many areas. As we now know that all compounds may cause toxicity according to the exposure time and dosage, toxicologists are primarily interested in the mechanisms of action of various agents. Nonetheless, scientists are currently trying to determine the routes or endogenous molecules that are affected by even the most well-known and ancient substances, which results in toxicity.