Pharmacodynamics is the branch of pharmacology that studies how drugs affect the body. It focuses on the mechanisms of action, including how drugs interact with receptors, enzymes, and other cellular targets to produce their effects. Understanding pharmacodynamics helps in determining the appropriate dosage and predicting the drug's efficacy and safety. This field also examines the relationship between drug concentration and its therapeutic effects, as well as potential side effects. By analyzing these interactions, researchers can develop better medications and optimize treatment plans for various conditions, enhancing patient outcomes in healthcare settings.