1.1 Introduction & History of Pharmacology

Pharmacology is the study of how drugs interact with living systems. From ancient herbal remedies to modern targeted therapies, understanding drug action has transformed medicine.

What is Pharmacology?

Definition

The science of drugs—their origin, composition, pharmacokinetics, therapeutic use, and toxicology.

Pharmacokinetics

What the body does to the drug: Absorption, Distribution, Metabolism, Excretion (ADME).

Pharmacodynamics

What the drug does to the body: Receptor binding, signal transduction, physiological effects.

Historical Milestones

~3000 BCE - Ancient Medicines

Sumerian clay tablets describe opium, Egyptian papyri list 700+ drugs.

1804 - Morphine Isolation

Sertürner isolates morphine from opium—first pure drug from natural source.

1897 - Aspirin Synthesized

Hoffmann at Bayer creates acetylsalicylic acid.

1928 - Penicillin Discovery

Fleming discovers first antibiotic, revolutionizing infectious disease treatment.

1950s - Receptor Theory

Clark and Ariens develop quantitative receptor pharmacology.

1990s - Genomic Era

Rational drug design, targeted therapies, personalized medicine begins.

Key Concepts

Drug

Any chemical that affects physiological function when administered to a living organism.

Receptor

Macromolecule (usually protein) that specifically binds a drug to produce a response.

Therapeutic Index

TD50/ED50 ratio—measure of drug safety. Higher = safer.

Selectivity

Drug's ability to affect one target over others. Key to minimizing side effects.