PAT201 Week 1

What is pharmacology?

What is pharmacology?

the study of medicines; effective use of drugs by a health care team depends on being able to apply knowledge related to:

• Anatomy & physiology

• Pathophysiology

• Chemistry

• Microbiology

• Clinical judgment

• Nursing process

Who is responsible for ensuring safety & quality of drugs, biologics, and natural health products?

Health Products and Food Branch (HPFB) of Health Canada

Why are Canadian drug regulations created?

to protect the public from drug misuse and provide a mechanism for quality assurance for safety and efficacy

1st step of Canadian drug approval:

Initial drug research is conducted

2nd step of Canadian drug approval:

Preclinical studies in cultured cells, living tissue, and species of animals are performed

3rd step of Canadian drug approval:

A clinical trial application (CTA) is submitted to Health Canada, followed by extensive clinical trials

• Phase I (the safety phase): small group of healthy humans

• Phase II (the effectiveness phase): small group of humans with the target disorder

• Phase III (the confirmation phase): larger groups of patients with the target disorder

• Phase IV (the monitoring phase): after the drug is approved and in the market, more information gathered on use, benefits, and risks

4th step of Canadian drug approval:

The pharmaceutical company completes a New Drug Submission (NDS) to Health Canada

• Safety and efficacy information, testing data, how the drug is produced/packaged, expected therapeutic benefits, adverse reactions

5th step of Canadian drug approval:

Drug experts (medical and drug scientists) review NDS for benefits and risks

6th step of Canadian drug approval:

Health Canada reviews information and passess it to healthcare providers and consumers

7th step of Canadian drug approval:

Health Canada issues a Notice of Compliance (NOC) and Drug Identification Number (DIN)

8th step of Canadian drug approval:

Health Canada monitors the efficacy of the drug and safety concerns after being marketed

• Regular inspection, notices, newsletters, feedback from consumers and healthcare providers

• Post-market evaluation

What is a drug?

chemical agent capable of producing biological responses within the body; given for purpose of producing a therapeutic response

What kind of responses can result from the use of drugs?

Responses could be desirable (therapeutic) or undesirable (adverse)

Define medication

a drug that is considered medically therapeutic

What are the 3 types of drugs?

1. Traditional drugs - produced by pharmaceutical manufacturers

2. Biologics - agents produced by animal cells and microorganisms

• Hormones, antibodies, vaccines, natural blood products

3. Natural health products

• Natural plant extracts - aloe

• Vitamins*,* minerals, herbals

• Dietary supplements

What are the 2 classifications of drugs?

Therapeutic and pharmacologic

What is therapeutic classification of drugs?

describes what is being treated by the drug

• Elevated blood pressure → antihypertensive drug class

• Clearly states what drug does clinically

• Therapeutic usefulness

What is pharmacologic classification of drugs?

the way the drug works at a molecular, tissue, body system level

• Addresses drug’s mechanism of action

• How a drug produces its effect in the body

  • A diuretic treats hypertension by lowering plasma volume

There are often many different but related versions of a drug

easy way to remember the difference between the classifications?

therapeutic - what it treats

pharmacologic - how it works

What is a prototype drug?

1st form of drug; representative drug from a class that is used as a point of comparison for related versions of that drug; well-understood drug

• Can allow nurses to extend knowledge to other similar drugs within that class with similar actions, effects, and adverse effects

  • Point of reference

• -coxib: celecoxib, parecoxib

• -parin: heparin, dalteparin

• -semide: furosemide, azosemide

What are the 3 types of nomenclature for drugs?

1. Chemical name - describes chemical structure of a drug

• diazepam/valium: 7-chloro-1,3-dihydro-1-methyl-5-phenyl-1,4-benzodiazepine-2(3H)-one

2. Generic name - adopted by regulatory agencies to describe active ingredient of a drug

• diazepam

3. Trade (proprietary/owndership or brand) name - used by company that produces a drug

• Valium

• Happens because drug patents last 20 years (other companies cannot manufacture the same drug for that amount of time) which gives a dominant company “ownership” over the drug they sell

Some characteristics of an ideal drug?

• Effectively prevents, treats, or cures condition of client

• Easy to administer

• Produces rapid, predictable response at relatively low doses

• Rapid onset of action

• Duration of action appropriate to reaching therapeutic goals

• Rapid elimination of drug

• No adverse effects

• No interactions with food or other drugs

• No contraindications; safe for all clients to take

Inexpensive and accessible

What are some of the different drug schedules?

• Schedule I: available only by prescription and provided by a pharmacist; includes:

  • All prescription drugs

  • Drugs with less potential for abuse: Schedule F

  • Controlled drugs: Schedule G

  • Narcotic drugs

• Schedule II: available only from a pharmacist; must be retained in an area with no public access

• Schedule III: available via open access in a pharmacy or pharmacy area (over the counter)

• Unscheduled: can be sold in any store without professional supervision

What is pharmacotherapy?

• The application of drugs to prevent disease and ease suffering

• Client experiences decreased s&s, more satisfaction of health status, and prevention of disease after pharmacological intervention

What are some things that the nurse should consider prior to administering drugs?

• Indication for use, mechanism of action, desired effects, adverse effects, interventions, contraindications

• Impact of client characteristics on pharmacotherapeutic response

• Client rights

• Providing appropriate education

What is the human integration pyramid model?

*refer to notes for image

• Categorizes functional environments in which clients exist

• Categories in model are interdependent and inter-related

  • Form basis of holistic approach to care

• Emphasizes the importance of holistic pharmacotherapy

• See the entire person aside from pharmaceuticals

What is pharmacogenomics?

• branch of pharmacology; studies role of genetic variation in drug responses

• Considers underlying genetic expression as reason for why drug therapy not effective for everyone

• Genetic differences discovered in drug-metabolizing enzymes (P450) have been discovered

  • Opens door to individualized drug therapy

  • Ultimate goal is to improve safety, efficacy of drug therapy through use of genetically guided treatment

Explain an example of the consequences of genetic poly morphisms

• Patient A has normal gene encoding for drug-metabolizing enzyme

• Patient B has genetic polymorphism for drug-metabolizng enzyme

  • Drug not metabolized and remains free in the plasma to produce enhanced effect or toxictiy