Scope Of Pharmacology

Scopes of Pharmacology

Pharmacology, as a broad field, is subdivided into several specialized disciplines. Each scope deals with a specific aspect of drugs or drug action.

1. Pharmacognosy

• The science of identifying and characterizing drugs of natural origin (mainly from plants or animals).
• Focuses on:
  • Sources of drugs
  • Purification and standardization
  • Structural elucidation of active constituents

2. Pharmacodynamics

• Study of “what the drug does to the body”.
• Conducted in the absence of disease to understand drug action.
• Includes:
  • Site of action
  • Biochemical pathways and reactions involved
  • Changes in physiology of organs/systems
  • Receptor interactions

3. Pharmacokinetics

• Study of “what the body does to the drug”.
• Deals with the movement of drugs through the body:
  • Absorption
  • Distribution
  • Biotransformation (Metabolism)
  • Excretion
• Determines onset, duration, and intensity of a drug’s action.

4. Pharmacotherapeutics

• Study of the use of drugs for treatment of diseases.
• Focuses on:
  • Choice of drug
  • Dosage
  • Duration
  • Expected outcomes and side effects

5. Therapeutics

• Broader term than pharmacotherapy.
• Involves all treatment modalities, including:
  • Drugs
  • Surgery
  • Radiation
  • Behavioral therapy
• Types:
  • Rational Therapeutics: Based on scientific understanding of disease and drug action.
  • Empirical Therapeutics: Based on experience or tradition without full understanding.
  • Symptomatic Therapeutics: Focuses on relieving symptoms rather than treating the cause (e.g., analgesics for pain).

6. Chemotherapy

• Focuses on drugs that selectively kill or inhibit pathogens (e.g., bacteria, fungi, parasites, cancer cells).
• Based on the principle of selective toxicity.
• Now also includes anti-cancer drug therapy.

7. Toxicology

• Study of harmful or poisonous effects of drugs and chemicals.
• Includes:
  • Acute and chronic toxicity
  • Poison management
  • Toxic dose and safety margin

8. Posology

• Science of drug dosing.
• Involves:
  • Dose: Quantity administered at one time.
  • Dosage: Regimen including dose, frequency, and duration.

9. Metrology

• Study of weights and measures in drug preparation and administration.
• Ensures accuracy and precision in pharmacological practice.

10. Pharmacoeconomics

• Evaluates the economic impact of drug therapy on:
  • Healthcare systems
  • Patients
  • Society
• Compares cost-effectiveness, cost-utility, and cost-benefit of therapies.

11. Pharmacovigilance

• The monitoring and detection of adverse drug reactions after drugs are marketed.
• Involves:
  • Prescription surveillance
  • Voluntary reporting systems
  • Population-level statistical analysis
• Ensures post-marketing drug safety.

12. Pharmacogenetics

• Studies individual genetic differences in drug response.
• Helps in identifying drug hypersensitivities or resistance in certain genotypes.

13. Pharmacogenomics

• A broader field combining:
  • Pharmacology + Genomics
• Uses genetic information to develop:
  • Personalized medicine
  • Gene-based drug therapy
  • Optimized dosages

14. Pharmacy

• A health-care profession concerned with:
  • Preparation
  • Standardization
  • Dispensing of drugs
• Closely related but distinct from pharmacology.

15. Materia Medica

• A historical term encompassing:
  • Pharmacognosy
  • Pharmacy
  • Posology
• Has now been largely replaced by the modern field of pharmacology.

16. Pharmacometrics

• Involves quantitative analysis of drug effects.
• Evaluates:
  • Drug efficacy
  • Side effects
  • Dose-response relationships
• Important in drug development and clinical trials.

17. Pharmacoepidemiology

• Study of the use and effects of drugs in large populations.
• Helps assess:
  • Drug safety
  • Effectiveness in real-world conditions
  • Post-marketing outcomes