PHARMACOLOGY · •The history of pharmacology began thousands of years ago with the use of plant...
Transcript of PHARMACOLOGY · •The history of pharmacology began thousands of years ago with the use of plant...
PHARMACOLOGY
Syllabus
• Lecturer: Asst. Prof. Ozan Tiryakioğlu
• Description: Examines pharmacological concepts and nursing practices required to provide safe and competent care. General principles of pharmacology, drugs actions at the physiological level, pharmacotherapeutics and administration will be studied.
• Grading Plan: 40% Midterm, 60% Final
• Sources: Rang & Dale’s Pharmacology (8E), Pharmacology
for Nurses (4E), Illustrated Pharmacology for Nurses
Course Schedule
• 10 weeks in total 1. Core Concepts
1. What is Pharmacology 2. Drug Classes 3. Drug Administration 4. Pharmacokinetics
2. Pharmacology and The Patient-Nurse Relationship
1. Medicaiton Errors 2. Substance Abuse and Emergency Preparedness
Course Schedule
3. Drugs used in neurological disorders
1. The Autonomic Nervous System
2. Seizures
3. Psychoses
4. Control of Pain
5. Anesthesia
6. Degenerative Diseases
Course Schedule
4. Cardiovascular and Urinary Systems 1. Lipid Disorders
2. Renal Failure
3. Hypertension
4. Heart Failure
5. The Immune System 1. Immune System Modulation
2. Inflammation and Fever
3. Infections
Course Schedule
6. The Respiratory System
1. Allergies
2. Asthma and other Pulmonary Disorders
7. The Gastrointestinal System
1. Peptic Ulcer
2. Bowel Disorders
3. Nutritional Disorders
Course Schedule
8. The Endocrine Sytem 1. Pituitary, Thyroid, and Adrenal Disorders
2. Diabetes Mellitus
3. Drugs for Male and Female Reproductive Systems
9. Integumentary System,Eyes, and Ears 1. Skin Disorders
2. Eye and Ear Disorders
10.Review
What is a drug?
• A chemical substance of known structure, other than a nutrient or an essential dietary ingredient*, which, when administered to a living organism, produces a biological effect.
• *Minerals and vitamins are dietary ingredients and can be considered as medicines.
• A medicine is a chemical preparation, which contains one or more drugs, administered with the intention of producing a therapeutic effect. Medicines usually contain other substances (solvents, etc.) besides the active drug, to make them more convenient to use.
• Many substances, such as insulin or thyroxine, are endogenous hormones but are also drugs when they are administered intentionally .
– Diabetes and Hypothyroidism
• Some drugs are experimental tools.
– Animal Cancer Models; Cadmium,
– DiethylnitrosamineLiver Cancer Inducer
• Before the advent of synthetic organic chemistry, pharmacology concerned itself exclusively with understanding the effects of natural substances, mainly plant extracts.
• Early pharmacologists focused most of their attention on such plant-derived drugs as quinine and digitalis.
• In the 20th century, synthetic chemistry began to revolutionise the pharmaceutical industry, and the science of pharmacology.
• Sulfonamidesfirst antibiotics. Discovered as a substance in dyes by german chemists. (1935).
• Elixir sulfanilamideAn improperly prepared sulfanilamide medicine.
– Mass poisoning in the United States in 1937.
– More than 100 deaths.
• Diethyl ether and Nitrous OxideUsed to liven up parties in 19. century.
• Since the 1980s, biotechnology has emerged as a major source of new therapeutic agents in the form of antibodies, enzymes and various regulatory proteins, including hormones and growth factors.
– produced by genetic engineering. (Insulin)
• Main goal of pharmacology: To understand what drugs do to living organisms, and how their effects can be applied to therapeutics
• What drugs do (Effect) How drugs work (Mechanism)
• PharmacologyPharmakon (Medicine), Logos (Study).
• As with other biomedical disciplines, the boundaries of pharmacology are not sharply defined.
• Biotechnology Biotechnology refers mainly to the use of recombinant DNA technology for a wide variety of purposes, including the manufacture of therapeutic proteins (antibiotic production from microorganisms)
• Pharmacogenomics The use of genetic information to guide the choice of drug therapy on an individual basis.
– Differences between individuals in their response to therapeutic drugs can be predicted from their genetic make-up.
– Genetic polymorphism of drug-metabolising enzymes or receptors (CYP genes).
• Pharmacoepidemiology This is the study of drug effects at the population level. It is concerned with the variability of drug effects between individuals in a population, and between populations
• Pharmacoeconomics This branch of health economics aims to quantify in economic terms the cost and benefit of drugs used therapeutically.
Classification of Therapeutics
• Substances applied for therapeutic purposes fall into one of the following three general categories:
– Drugs or medications.
– Biologics.
– Complementary and alternative medicine (CAM) therapies
• A drug is a chemical agent capable of producing biologic responses within the body. These responses may be desirable (therapeutic) or undesirable (adverse). After a drug is administered, it is called a medication.
• Biologics are agents naturally produced in animal cells, by microorganisms, or by the body itself. Examples of biologics include hormones, monoclonal antibodies, natural blood products and components, and vaccines.
• Complementary and alternative medicine (CAM) therapies. These involve natural plant extracts, herbs, vitamins, minerals, dietary supplements.
Phases of Approval for Drugs
1. Preclinical investigation.
2. Clinical investigation.
3. Review of the New Drug Application (NDA).
4. Postmarketing surveillance
Preclinical Investigation
• Preclinical investigation involves extensive laboratory research. Scientists perform many tests on human and microbial cells cultured in the laboratory. Studies are performed in several species of animals to examine the drug’s effectiveness at different doses and to look for adverse effects.
• Extensive testing on cultured cells and in animals is essential because it allows the pharmacologist to predict whether the drug will cause harm to humans.
• Because laboratory tests do not always reflect the way a human responds, preclinical investigation results are always inconclusive.
• Animal testing may overestimate or underestimate the actual risk to humans.
Clinical Investigation
• The second phase of drug testing, takes place in three different stages termed clinical phase trials. Clinical phase trials are the longest part of the drug approval process.
– Large groups of selected patients with the particular disease are then given the medication
– drug is effective?, worsens other medical conditions? , interacts unsafely with existing medications?
NDA review
• The average NDA review time for new drugs is approximately 17 to 24 months.
– If the NDA is approved, the process continues to the final phase. If the NDA is rejected, the process is suspended until noted concerns are addressed by the pharmaceutical company.
Postmarketing surveillance
• The final phase of the drug approval process, begins after clinical trials and the NDA review have been completed.
– The purpose of this phase is to survey for harmful drug effects in a larger population. Some adverse effects take longer to appear and are not identified until a drug is circulated to large numbers of people.
Nurses and the Drug Approval Process
• In nursing, it is during the postmarketing surveillance period that the nurse has the most frequent opportunities to participate in the drug approval process. – Whenever a possible drug reaction is noted, the nurse
is responsible for reporting the reaction to the prescriber and appropriate health care agency personnel
– By monitoring for and reporting adverse effects, the nurse can ensure that better postmarketing surveillance is achieved.
Review
• The history of pharmacology began thousands of years ago with the use of plant products to treat disease.
• Pharmacology is the study of medicines. It includes the study of how drugs are administered and how the body responds.
• Therapeutic agents may be classified as drugs, biologics or complementary and alternative medicine (CAM) therapies.
Review
• Drug regulations were created to protect the public from drug misuse and to assume continuous evaluation of safety and effectiveness
• There are four phases of approval for therapeutic and biologic drugs. From cellular and animal testing to use of the experimental drug in patients.
• Nurses may participate in several phases of the drug approval process but will have the most frequent opportunities during Phase 4, postmarketing surveillance.
Drug Classes
• Therapeutic Classification Based on therapeutic usefulness.
• Pharmacologic classification Refers to the way a drug works at the molecular, tissue, and body system levels.
• antidepressants, antipsychotics, antineoplastics.
• The pharmacologic classificationmechanism of action
– how a drug produces its physiological effect in the body
Prototype Drugs
• Well-understood drug model with which other drugs in its representative class are compared.
• Not always the most effective
Drug Names
• Chemical Name
• Generic Name
• Trade Name
Chemical Name
• International Union of Pure and Applied Chemistry (IUPAC).
• Diazepam (Diazem) 7-chloro-1,3-dihydro-1-methyl-5-phenyl-2H-1,4-benzodiazepin-2-one
• Nurses rarely use chemical name.
• Usefull chemical names:
– Lithium carbonate,sodium chloride.
• Chemical group name:
– cephalosporins.
Generic Name
• Less complicated, easier to remember
• WHO uses generic names
• One generic name for each drug
Trade Name
• Brand name
• Short, easy to remember
• Exclusive ownership under brand name
– 17 years including FDA submission.
– No generic equivalent may be produced
• Generic namelowercase
• Brand nameCapitalized
• Brand vs GenericBioavailabity
– Bioavailability is the physiological ability of the drug to reach its target cells and produce its effect
• Circulatory shock 5 mins difference between brand and generic is significant
• Headache relief5 mins is not as significant
• A student nurse is preparing medications for the patient. When checking the medication administration record against the drug found in the patient’s medication cassette, the student nurse notes that hydroxyzine has been ordered for the patient, but hydralazine has been dispensed from the pharmacy. What should the student nurse do?
• A student nurse is preparing medications for the patient. When checking the medication administration record against the drug found in the patient’s medication cassette, the student nurse notes that hydroxyzine has been ordered for the patient, but hydralazine has been dispensed from the pharmacy. What should the student nurse do?
• HydroxyzineAntihistaminic • Hydralazine Antihypertensive • hydrOXYZINE” and “hydrALAZINE”
Controlled Substances
• Dependence
– Physical vs Psychological
• Physical Adaptation of the nervous system to repeated drug use. Withdrawal. Discomfort
• PsychologicalNo physical discomfort.
• Scheduled Drugs5 Categories
Teratogenic Drugs
• A teratogen is a substance that has the potential to cause a defect in an unborn child during pregnancy.
• Categories A, B, C, D, and X
• A Safest, XMost Dangerous
Review
• Drugs may be organized by their therapeutic or pharmacologic classification
• Drugs have chemical, generic, and trade names. A drug has only one chemical or generic name but may have multiple trade names.
• Generic drugs are less expensive than brand-name drugs, but they may differ in their bioavailability; that is, the ability of the drug to reach its target tissue and produce its action.
• Drugs with a potential for abuse are restricted by the Controlled Substances Act and are categorized into schedules. Schedule I drugs are the most tightly controlled; Schedule V drugs have less potential for addiction and are less tightly controlled. Category A drugs are the safest to take during pregnancy. Category X drugs are the most dangerous.
Principles of Drug Administration
• Nurses are expected to understand the pharmacotherapeutic principles for all medications given to each patient.
Responsibilities
• What drug is ordered.
• Name (generic and trade) and drug classification.
• Intended or proposed use.
• Effects on the body.
• Contraindications.
• Special considerations (Age, weight, body fat distribution, and individual pathophysiological states).
• Side effects.
• Why the medication has been prescribed for this particular patient.
• How the medication is supplied by the pharmacy.
• How the medication is to be administered, including dosage ranges
• Before any drug is administered;
– medical history, physical assessment, disease processes and special needs.
• What a nurse can do?
– Preventable adverse effect: Experience and knowledge
– Not Preventable: be prepared to recognize and respond
Serious Side Effects
• Allergic and Anaphylactic reactions
• Allergic reactionAn acuired hyperresponse reaction of body defenses to a foreign substance
– Rash, İtching, runny nose, edema
• Anaphylactic reaction Severe type of allergic reaction that involves the massive, systemic release of histamine and other chemical mediators of inflammation that can lead to life threatening shock.
– acute dyspnea, sudden hypotension, tachycardia
• Ensuring patient safety:
– 5 RIGHTS
– 3 CHECKS
Five Rights of drug administration
1. Right patient.
2. Right medication.
3. Right dose.
4. Right route of administration.
5. Right time of delivery
Three Checks of drug administration
1. Checking the when removing it from the medication drawer, refrigerator, or controlled substance locker.
2. Checking the drug when preparing it, pouring it, taking it out of the unit-dose container, or connecting the IV tubing to the bag.
3. Checking the drug before administering it to the patient.
• Pharmacotherapeutic success depends on compliance
– not taking the medication at all
– taking it at the wrong time
– in the wrong manner.
• Informing the patient about risks and benefits
Time Schedules
• STAT
• ASAP
• PRN
• Routine
• Single
• STAT (Lat. Statim); Immedeatly.
• Time between order and administration should no exceed 5 mins.
• ASAPAs Soon As Possible.
• Time between order and administration should no exceed 30 mins.
• Single Order Given only once at a specific time.
• Prn Order (Lat. Pro re nata)Means ‘as the circumstance arise’
• Orders not written as STAT, ASAP, NOW, or PRN are called routine orders.
– within 2 hours of the time the order is written
• Tylenol 325 mg PO every 6 hours PRN sore throat
• Tonsillectomy
• Documentation should be completed only after administraton
– Drug name
– Dosage
– Time
– Signature
Before Administration
• Verify the medication order and check for allergy history on the chart.
• Wash your hands and apply gloves, if indicated.
• Use aseptic technique when preparing and administering parenteral medications
• Identify the patient
• Ask the patient about known allergies
• Inform the patient
– name of the drug, the expected actions, adverse effects
• Position the patient for the appropriate route of administration
• Do not leave drugs at the bedside
Routes of Administration
• 3 main routes of administration
– Enteral
– Parenteral
– Topical
Enteral Drug Administration
• OrallyTablet,Capsule, Liquid
• Nasogastric / gastronomy tubes
• Safest route
• No skin barrier, vast absortive membranes (oral mucose, stomach, intestine)