Understanding Pharmacology for Health Professionals, Sixth Edition, Chapter 1, Introduction to Pharmacology

Chapter 1: Introduction to Pharmacology

Learning Objectives

• 1.1 Describe the origin and meaning of pharmacology, drug, medicine, and Rx.

• 1.2 Describe the medical uses of drugs.

• 1.3 Describe types of pharmacies and roles of the pharmacist and pharmacy technician.

• 1.4 Describe how drugs are discovered or created.

• 1.5 Differentiate between the chemical, generic, and trade names of a drug.

• 1.6 Differentiate between prescription drugs, Schedule drugs, over-the-counter drugs, and dietary supplements with examples.

• 1.7 Describe the categories of controlled substances and give examples.

• 1.8 Describe the use of orphan drugs and designer drugs.

• 1.9 Demonstrate mastery of the chapter by completing the Chapter Review Exercises.

Introduction to Pharmacology

• Definition: Pharmacology is the study of drugs and their interactions with living organisms.

  • Origin of the term: Greek pharmakon means "drug" or "medicine".

• Scope: Covers diverse topics such as:

  • Botany, Chemistry, Genetics, Toxicology, Addiction, Legislation, and Patient education.

• Historical Context of Drugs: The term "drug" comes from the Dutch word droog, referring to dried herbs. Early drugs had little documented legitimate use.

• Medicine: The Latin word for drug is medicina, meaning remedy or cure.

Medical Uses of Drugs

• Drugs serve three primary medical purposes:

  • Prevent disease: Prophylaxis exemplified by vaccinations and preemptive medications for conditions like motion sickness.

  • Diagnose disease: Used in conjunction with tests, e.g., contrast dyes in x-rays.

  • Treat diseases: Aimed at controlling or curing symptoms and conditions, such as analgesics for pain.

Historical Development of Drugs

• Ancient Civilizations: Pharmacology is one of the oldest branches of medicine:

  • Mesopotamia: Use of clay tablets to document drug usage around 5000 BC.

  • China: Herbal medicines developed alongside acupuncture and massage, with early recorded remedies from 3494 BC.

  • Egypt: The Ebers Papyrus (1500 BC) listed numerous herbal formulations.

  • Aztecs and Native Americans: Utilized gardens and native plants for medicinal purposes.

  • Middle Ages: Use of both valid and harmful substances, with limited anatomical understanding.

Drugs from 1700 to 1900

• Many drugs contained unlisted addictive ingredients, leading to widespread addiction.

• Apothecary: Originating from the Greek term for storehouse, apothecaries played a key role in medicine by compounding customized drugs.

• Pharmacopeia: Lists of drugs detailing individual ingredients and preparation methods were essential for standardizing medications.

• Chemists began isolating pure substances, significantly advancing pharmacological knowledge.

Today’s Pharmacy Environment

• Pharmacy Definition: Originates from Greek as "preparer of drugs", pharmacies serve as key sites for receiving and dispensing medications.

• Types of Pharmacies:

  • Hospital pharmacies: Specialize in inpatient care, offering comprehensive drug supplies.

  • Outpatient pharmacies: Found in clinics and provide services for external patients.

  • Community pharmacies: Retail venues that provide prescription and over-the-counter medications.

  • Online pharmacies: Offer convenience, ensuring medications are shipped directly to patients.

Role of Pharmacists and Pharmacy Technicians

• Pharmacist: A healthcare professional responsible for managing pharmacy operations, medication dispensing, and patient consultations.

• Pharmacy Technician: Supports pharmacists by filling prescriptions, labeling, and providing customer instructions under supervision.

• Licensing requirements vary: Pharmacists need a PharmD and state licensure; technicians must pass a certification examination.

Drug Discovery and Creation

• Many modern drugs are derived from natural sources like plants, animals, and minerals, while advancements in molecular and genetic manipulation have transformed drug development.

• Understanding genetic factors can enhance drug efficacy and personalization of treatments, exemplified by pharmacogenetics and recombinant DNA technology.

Types of Drugs

• Prescription Drugs: Require a valid prescription from a licensed healthcare provider.

• Schedule Drugs: Classified based on potential for abuse; includes controlled substances.

• Over-the-Counter Drugs (OTC): Available without prescriptions, deemed safe if directions are followed.

• Dietary Supplements: Must comply with regulations for labeling and safety.

• Orphan Drugs: Developed for rare diseases with incentives provided under the Orphan Drug Act.

• Designer Drugs: Illegal substances created to mimic effects of controlled drugs, with regulations addressing these through the Federal Analogue Act.