Pharmacology and Drug Development Overview

History of Pharmacology

• Pharmacology began when human ancestors discovered that consuming specific plants altered body functions and awareness.
• Indigenous peoples have used medicinal plants for centuries; they have identified over 400 different species of plants, lichens, fungi, and algae with medicinal properties.
• Europeans adopted many Indigenous plant medicines, like the "tree of life" used to cure scurvy by Jacques Cartier's crew.
• Indigenous peoples also learned to use medicines from Europe and other parts of the world.

Drug Development Phases

• Preclinical Stage: Testing on animals lasting three years to assess carcinogenicity, teratogenicity, and drug breakdown and elimination.
• Clinical Stage: Human trials requiring Investigational New Drug (IND) approval.
  • Phase 1: Small, increasing doses on limited subjects, testing safety, drug toxic effects, and dose range.
  • Phase 2: Larger number of subjects, testing dose range and effectiveness, adverse reactions reported to the FDA.
  • Phase 3: Large number of subjects, testing safety, dose, and efficacy.
• NDA Review: New Drug Application (NDA) approval required before proceeding to postmarketing surveillance.
• Postmarketing Surveillance (Phase 4): Drug released and marketed under supervision. Toxicity is monitored, and the drug may be removed from the market if serious issues arise.

Drug Naming

• Chemical Name: Describes the drug's chemical composition.
• Generic Name: Non-proprietary name assigned by the manufacturer.
• Trade Name: Brand name given by the manufacturer, marketed under this name.
• Brand Name: Commercial name used for marketing.

Drug Regulations

• Canadian Classification of Drugs and Drug Scheduling: Drugs classified into unscheduled, Schedule 1, Schedule 2, or Schedule 3.
  • Unscheduled Drugs: Sold without professional intervention; considered safe and effective for self-selection, like acetaminophen, ibuprofen, and aspirin.
  • Schedule 3 Drugs: Can be bought without a prescription but sold only in pharmacies, like fluorides for caries prevention.
• US Scheduled Drugs: Controlled substances divided into five schedules based on abuse potential.

Role of Registered Dental Hygienist (RDH) in Prescription Writing

• Responsibilities:
  • Checking for errors.
  • Answering client questions.
  • Giving client instructions, including dosage, duration, frequency, reason, side effects, and interactions, with repetition for confirmation.
  • Charting all information.
  • Monitoring for drug shoppers.
  • Safeguarding prescription pads and drugs.

Modern Format for Prescriptions

• Heading: Contains the prescribing professional's details (name, address, phone number), the client's details (name, address, phone number, age), and the date.
• Body: Contains the Rx symbol, drug name and dosage, amount to be dispensed, directions to the client, and an example.
• Closing: Includes the prescriber's signature, drug enforcement number, and refill instructions.

Case Study: Periodontitis Treatment and Client Adherence

• A 36-year-old female with a periodontal abscess received treatment, including ibuprofen, penicillin, and chlorhexidine rinse prescription.
• Client's adherence was poor; she stopped taking the antibiotic and mouthwash due to side effects and not fully understanding the importance of completing the full course of treatment.
• Case highlights the need for thorough patient education on proper medication use, side effects, and the importance of adherence, especially with antibiotics.