N319 Introduction to Pharmacology 1. History of Pharmacology Babylonians John Jacob Abel 2. Sources of medications Plants -Alkaloids, Glycosides, Gums, Oils Animals/Humans Minerals Chemicals- primary source today 3. Pharmacology the study of medicines Prerequisites Characteristics 4. Pharmacology and Therapeutics Pharmacology Therapeutics Pharmacotherapy 5. Drug Classifications Drug Medication Biologics Complementary and Alternative 6. Therapeutic and pharmacologic classification of drugs Therapeutic classification Pharmacologic classification 7. Names of drugs Chemical- chemical composition Generic- universal name Trade/Brand- assigned by the manufacturer once released on the market 8. Types of drug therapyPrescription drugs Nonprescription drugs Controlled drugs Recreational drugs 9. Trade vs Generic drugs Cost Bioavailability 10. Drug Approval Intro 1 1906— Pure Food and Drug Act: protected the public from mislabeled products 1938— Food Drug & Cosmetic Act: made sure there was no harmful effects 1951— Durham-Humphrey Amendment to FDCA: separated prescription vs nonprescription drugs 1970— Controlled Substance Act (know table 2.1): created 5 schedules for controlled substances 1983— Orphan Drug Act: funds were given to companies to research drugs that were uncommon 1997— Food and Drug Modernization Act: Fast track system, off-label uses of drugs, use of children in studies. Black Box Warnings 2003-- Health Insurance Portability and Accountability Act (HIPAA): protected patient privacy 2010-- Patient Protection and Affordable Care Act: Obama Care 11. Regulatory Agencies Food & Drug Administration (FDA): oversees all medications Drug Enforcement Agency (DEA): controls all controlled substances Centers for Disease Control (CDC): controls chemical warfare American Nursing Association (ANA): regulates the nursing education and practice State Board of Nursing Nurse Practice Act Misfeasance- when you give a wrong medicine or dose Nonfeasance- when you forget to give a medication Malfeasance- when you give the right drug in the wrong route 12. Sources of Drug Information U.S. Pharmacopeia (USP)- USP Label. Drug must be of high standard to be listed. 3 volume set published annually with 2 supplements. Information: strength, quality, purity, packaging, safety, labeling, dosage form. National Formulary- Supplement to the USP PDR- Used by a variety of HCP. Lists pharmaceutical companies, color pictures of meds. Drug action, recommended dosage, indications for use, side effects. Nursing Drug Handbooks- Generic and trade names. Indication for use & recommended doses. Action & pharmacokinetics. Side effects & nursing implications, teaching tips. Internet- Action, indications, side effects, when to contact MD. May or may not be at patient’s level of understanding. May not contain accurate information. Pharmaceutical Companies- Drug samples, teaching handouts. 13. Drug development and approval Pre-clinical testing- Extensive animal studies for safety, biological activity, and formulations Submit Investigational New Drug (IND) application-Application reviewed by FDA Clinical testing- Human studies (10 years or older) Phase I- Studies the kinetics, determine safety, and dosage ranges of the drug on a small group of healthy volunteers (20-100) Phase 2- Evaluate effectiveness and identifies side effects of the drug on a small number of individuals with the disease (100 to 500) Phase 3- Studies the safety and efficacy of the drug on a large number of individuals with the disease (1000 to 5000). Placebo-controlled studies, blind investigational drug studies, doubleblind placebo-controlled studies Submit a new drug application (ND) to FDA Phase 4- Post market studies-Long-term uses, additional uses Intro 2 14. Informed Consent Nuremburg Code- rights of human subjects to be protected in medical research Informed Consent- Describes the study in detail. Hazards, risks, and benefits of study. Payment. Study termination. Confidentiality Role of the nurse- Inform the patient of all the details of the study Basic Tasks for obtaining Informed Consent- Decision Making Capacity. Information/Education. Understanding. Free-Choice. Obtain informed consent. Documentation. 15. Pregnancy and Lactation Label Changes Letter categoriesRisk summary16. The Nursing Process Assessment--Gather data: Subjective- health history, drug history Objective- physical exam, lab data, diagnostic tests Nursing Diagnosis-NANDA List Identify health care needs of clients- actual or potential within the realm of nursing practice Nursing diagnosis related to drug therapy- Knowledge deficit, noncompliance, or diagnosis related to side effects Alteration in tissue perfusion r/t decrease oxygen supply to coronary arteries 20 to CAD Knowledge deficit r/t diuretic therapy 20 to new tx regimen. Planning (establishing goals) S- specific to patient M- measurable A- attainable R- realistic T- time limited Pt will lose 5# within 3 days Pt will demonstrate proper administration techniques of medications prior to discharge Implementation/Interventions Knowledge necessary before administering drug therapy- Goals of drug therapy, Mechanism of drug action, Expected effects, Proper administration techniques, Contraindications Patient Education- Why are they taking it? What is the intended therapeutic response? How should the medication be taken? How often should the medication be taken? What side effects will occur and which to report to HCP? Medication orders Components of a Drug Order- date and time, patient name and hospital number, drug name, dosage, route and frequency, MD name, nurses name and title Prescriptions (# refills, duration, #dispense) Types of Drug orders Written orders vs Fax orders Phone orders vs Verbal orders- must repeat to the provider Standing order- MD has these for all patients; routine orders Administration of medications 30-minute window 5 rights of medication administration- Right patient (identify by two methods), right drug, right dose, right time, right route Intro 3 Documentation- Date, time, med, dose, route Withholding medication- Patient refuses, side effects. Notify physician and document; educate the patient on effects of not taking the medication Evaluations-Evaluate effectiveness of medications for therapeutic and non-therapeutic responses30 minutes to an hour after administering Determine the extent to which goals of care have been achieved. How did the client respond to the interventions? Compare client response to outcome and document responses Analyze reasons for results and conclusions Modify care plan Basic Principles of Pharmacology 1. 3 Phases of Drug Action Pharmacokinetic Phase- what the body does to the drug Pharmacodynamic Phase- what the drug does to the body Pharmacotherapeutic Phase- side effects of the drugs 2. Pharmacodynamic Phase What is pharmacodynamics? Describes the biochemical, physiologic action, and effects of drugs in the body; occurs when the drug reaches its target cell, tissue, organ generating its effect; cannot create a new response in the body Frequency Distribution Curve ED50- the average dose that produces half of the desired response on most patients (recommended dose) Objective measurements- antihypertensive drug; ED50 is the dose that reduces BP by one half of the number of mmHg above normal (single patient) Subjective measurements- Nausea medication; ED50 is the dose that produces relief of nausea in half of the test subjects (100’s of subjects required) LD50- produces death in one half of the test animals Therapeutic Index- the middle of the ED50 and LD50; TI= LD50/ED50 Margin of Safety- TI provides a drug’s margin of safety; the wider the curve the safer the drug Drug Response Curve 3 phases Phase 1- lowest dosage range that produces a clinical response Phase 2- increase in dosage produces an increased response Phase 3- dosage effects have reached 100% of their therapeutic effects Potency- the measurement of the amount of active ingredient of the drug; the drug with the least amount of active ingredient producing its ED50 is more potent Efficacy- the drugs ability to produce an effect; maximum efficacy is the maximum effect that a drug can produce Objective is to select drugs that have a very narrow and well-defined target or very specific action in the body. The narrower the action, the less widespread damage (i.e., adverse effects). Theories of Drug Action Nonspecific Theory- Medications that influence and change the environment of cells. Five mechanisms Alteration of body chemistry (pH, osmotic pressure, electrolytes). Absorption of toxins/drugs, electrolytes, bile salts, in the intestinal tract Intro 4 Create a physical barrier Lubricates cells Alters surface tension Drug Enzyme Theory- 2 forms of Drug-enzyme interaction A drug may bind to the same physical location on the enzyme, preventing the enzyme from functioning normally. A drug may interact with an enzyme target changing the physical structure of the enzyme and disrupting its integrity. Drug Receptor Binding Agonist Drugs- mimics the normal response of the natural chemical Antagonist Drugs- blocks the natural chemical from binding which creates the opposite effect of the normal response Upregulation- more receptors; happens with antagonists Downregulation- less receptors; happens with agonists 3. Pharmacotherapeutics Types of therapy Acute- New or immediate problem. (Appendicitis) Maintenance- Maintains current functions, does not prevent progression. (Insulin, BP meds) Supplemental- Maintains normal functions. (Vitamins, Protein drinks) Supportive- Maintains body function integrity. (IV fluids) Prophylactic- Preventive care. (Antibiotics prior to surgery) Palliative- End of life care, comfort measures. (Pain medications) Adverse Drug Reactions (ADRs) TYPE A: Intrinsic Adverse Drug Reaction-A direct (excessive) extension of the known pharmacodynamic actions. Intrinsic ADR's are the most common type of ADR (60-70% of all known ADR's), predictable, and dose-dependent Define the following Type A ADRs: Toxic Reaction- Toxic Reactions are physical reactions resulting from exposure to a poisonous chemical Tachyphylaxis- rapidly diminishing response to successive doses of a drug, rendering it less effective. The effect is common with drugs acting on the nervous system. Drug Tolerance- A condition that occurs when the body gets used to a medicine so that either more medicine is needed or different medicine is needed. Additive/Synergistic Effects- occurs when the combined effect of two or more chemicals is equal to the sum of the effect of each agents given alone Antagonistic Effects- A biologic response to exposure to multiple substances that is less than would be expected if the known effects of the individual substances were added together. TYPE B: Idiosyncratic Adverse Drug Reaction -An uncommon, unpredictable ADR that is not explained by pharmacodynamics, 20-30% of all ADR's, independent of the size of the dose of drug administered, may be genetically linked. Define the Following Type B ADRs: Allergic reaction/Anaphylaxis- The hypersensitive response of the immune system of an allergic individual to a substance. When an allergen enters the body, it causes the body's immune system to develop an allergic reaction in a person with an allergy to it. Idiosyncratic Response- adverse effects that cannot be explained by the known mechanisms of action of the offending agent, do not occur at any dose in most patients, and develop mostly unpredictably in susceptible individuals only. Intro 5 Carcinogenic Effect- a chemical substance or a mixture of chemical substances which induce cancer or increase its incidence. Teratogenic Effect- the ability of a drug to cause fetal abnormalities or deformities. Extrapyramidal Effect- describe the side effects caused by certain antipsychotic and other drugs. These side effects include involuntary or uncontrollable movements. tremors. Serum sickness- The immune system reacts to medicines that contain proteins used to treat immune conditions. It can also react to antiserum, the liquid part of blood that contains antibodies given to a person to help protect them against germs or poisonous substances. Fetal alcohol Syndrome- a condition in a child that results from alcohol exposure during the mother's pregnancy. Fetal alcohol syndrome causes brain damage and growth problems. The problems caused by fetal alcohol syndrome vary from child to child, but defects caused by fetal alcohol syndrome are not reversible. Iatrogenic Reaction- Due to the activity of a physician or therapy. For example, an iatrogenic illness is an illness that is caused by a medication or physician Define the Following Terms Photosensitivity- Oversensitivity of skin to light. Photosensitivity can be a side effect of medications or result from diseases, such as lupus. Treatment depends on the severity of the reaction and the cause. Photosensitivity can be prevented by avoiding skin exposure to ultraviolet light. Incompatible- an undesirable reaction that occurs between the drug and the solution, container or another drug Polypharmacy- regular use of at least five medications, is common in older adults and younger at-risk populations and increases the risk of adverse medical outcomes. There are several risk factors that can lead to polypharmacy Placebo- a pharmacologically inactive substance that can have a therapeutic effect if administered to a patient who believes that he or she is receiving an effective treatment. Intro 6
