PHARMACOLOGY
ESSENTIALS
A Comprehensive 4-Chapter E-Book
Authored by Gemini Medical Sciences
Page 1
, Chapter 1: Introduction to General
Pharmacology
Pharmacology is the study of substances that interact with living systems through chemical
processes. It is divided into two major branches.
1.1 Pharmacokinetics (PK)
Pharmacokinetics describes what the body does to the drug. It involves the ADME
process:
• Absorption: Movement of a drug from its site of administration into the central
compartment.
• Distribution: The process by to which a drug reversibly leaves the bloodstream and
enters the interstitium.
• Metabolism: Chemical alteration of the drug in the body (primarily by the liver).
• Elimination: The removal of the drug from the body (primarily via kidneys).
Key Concept: Bioavailability
The fraction of an administered dose of unchanged drug that reaches the systemic
circulation.
F = (AUC_{oral} / AUC_{IV}) × 100%
Chapter 2: Pharmacodynamics &
Mechanisms
Pharmacodynamics is the study of the biochemical and physiological effects of drugs and
their mechanisms of action (what the drug does to the body).
Page 2
ESSENTIALS
A Comprehensive 4-Chapter E-Book
Authored by Gemini Medical Sciences
Page 1
, Chapter 1: Introduction to General
Pharmacology
Pharmacology is the study of substances that interact with living systems through chemical
processes. It is divided into two major branches.
1.1 Pharmacokinetics (PK)
Pharmacokinetics describes what the body does to the drug. It involves the ADME
process:
• Absorption: Movement of a drug from its site of administration into the central
compartment.
• Distribution: The process by to which a drug reversibly leaves the bloodstream and
enters the interstitium.
• Metabolism: Chemical alteration of the drug in the body (primarily by the liver).
• Elimination: The removal of the drug from the body (primarily via kidneys).
Key Concept: Bioavailability
The fraction of an administered dose of unchanged drug that reaches the systemic
circulation.
F = (AUC_{oral} / AUC_{IV}) × 100%
Chapter 2: Pharmacodynamics &
Mechanisms
Pharmacodynamics is the study of the biochemical and physiological effects of drugs and
their mechanisms of action (what the drug does to the body).
Page 2
