PHA 338 - Lecture 1 (Part A) Fundamentals

Drug vs Medicine

A drug is the active therapeutic substance, while a medicine includes the drug plus excipients (inactive ingredients)

Pharmaceutical Sciences

A broad field that includes pharmacology, pharmaceutics, medicinal chemistry, pharmacokinetics, pharmacodynamics, pharmacogenomics, toxicology, and biophysics/physical chemistry that studies drugs and their interactions with the body

Pharmacodynamics

Study of the interaction of a drug with its receptor and its effects on the body (“what the drug does to the body”)

Pharmacokinetics

Study of the body’s response to a drug and its effects on the drug (“what the body does to the drug”)

Drug

A therapeutic agent; any substance other than food used in the prevention, diagnosis, alleviation, treatment, or cure of disease

Medicine

A broader term that includes the active drug plus nonmedicinal ingredients (excipients) used for pharmaceutical purposes

Chemical Name

The precise chemical description of a drug’s structure

Pharmacologic Name (Generic Name)

The standardized nonproprietary name assigned by organizations like USAN (e.g., lisinopril)

Brand Name (Proprietary Name)

The trademarked name given by a pharmaceutical company (e.g., Prinivil®, Zestril®)

Company Code Name

A temporary name used during drug development (e.g., MK-521)

Drug-Target Complex

Formed when a drug binds to its receptor, causing both to change shape (conformation) and trigger a biological response

Drug Action Mechanism

A drug binds to a receptor → drug-receptor complex forms → conformational changes occur → biochemical events are triggered → biological response is produced

Molecular Targets for Drugs

Proteins (receptors, ion channels, enzymes, transporters), nucleic acids, lipids, and carbohydrates

Primary Drug Targets (Focus)

Proteins and nucleic acids are the main targets studied in this course

Covalent Bonds

Strong, often irreversible bonds formed by sharing electrons between drug and target

Ionic Bonds

Electrostatic attraction between oppositely charged ions

Hydrogen Bonds

Weak interactions between hydrogen and electronegative atoms (O, N, F)

Dipole-Dipole Interactions

Attraction between polar molecules

Ion-Dipole Interactions

Attraction between an ion and a polar molecule

van der Waals Interactions

Very weak, short-range interactions due to temporary dipoles

Hydrophobic Interactions

Nonpolar molecules cluster together to avoid water

Halogen Bonds

Interaction involving halogen atoms contributing to binding specificity

Drug Classification Methods

Molecular structure, pharmacologic/physiologic effects, mechanism of action, target systems, and company products

Drug Sources

Animals (e.g., insulin), plants (e.g., atropine), synthetic derivatives, and genetic engineering

Cellular Sites of Drug Action

Drugs interact at structures like the cell membrane, cytoplasm, and organelles