:1 Introduction to Pharmacologic Concepts Lecture 1 Part 1 This lecture is intended solely for the education of Grossmont College nursing students enrolled in Pharmacology 118. It may not be reproduced or distributed. PHARMACOLOGY118


Pharmacology and the Nursing Process :2 Pharmacology and the Nursing Process The Nursing Processis crucial for safe medication administration. “Crucial = of the greatest significance in determining an outcome”


Pharmacology and the Nursing Process :3 Pharmacology and the Nursing Process Nursing Process draws together all of the aspects of the patient: Physical Cultural Cognitive Spiritual Sexual Financial Recognizing these aspects allows for a more holistic approach to patient care


The Nursing Process :4 The Nursing Process A research-based organizational framework for professional nursing practice Central to all nursing care Encompasses all steps taken by the nurse in caring for a patient Ongoing and constantly evolving process Critical thinking Flexibility is important


The Nursing Process :5 The Nursing Process Assessment Nursing diagnosis Planning Goals Outcome criteria Implementation Evaluation


Nursing Process :6 Nursing Process Assessment Data collection -Subjective, objective - Accurate


Nursing Process :7 Nursing Process Nursing diagnosis Decision about the need/problem (actual or at risk for) Three parts Human response to illness “related to” “as evidenced by”


Nursing Process :8 Nursing Process Nursing diagnosis critical thinking creativity accurate data collection It is a statement about the patient’s status and will guide nursing interventions


Nursing Process :9 Nursing Process Planning Identification of goals -Must be patient-centered Outcome criteria -Must be specific, objective, measurable, realistic -have a time frame Prioritization


Nursing Process :10 Nursing Process Implementation Initiation and completion of the nursing care plan as defined by the nursing diagnoses and outcome criteria


Nursing Process :11 Nursing Process Evaluation Ongoing part of the nursing process Determining the status of the goals and outcomes of care


The Nursing Process and Medication Administration :12 The Nursing Process and Medication Administration Assessment 1. Health- allergies pattern of health care experiences/ illnesses level of education understanding of the disease process financial support 2. Physical assessment – age and weight social support at home chronic conditions 3. Diagnostic Tests, lab values 4. Medication History Prescriptions OTCs Herbals Responses to medications (therapeutic and adverse responses)


The Nursing Process and Medication Administration :13 The Nursing Process and Medication Administration Nursing Diagnosis Human response to illness (actual or risk) drug therapy may only be a small part of the total pt picture or, at times it may be an all consuming factor in the patient’s life Drug therapy is incorporated into the total picture


The Nursing Process and Medication Administration :14 The Nursing Process and Medication Administration Planning 1. Identification of possible interactions knowledge of the prescribed medication over-the-counter (OTC) drugs, herbs 2. Client and family education level of patient understanding of disease level of education 3. Gather equipment, review procedures, safety measures timing and frequency of drugs storage of drugs This phase leads to the provision of safe effective medication administration


The Nursing Process and Medication Administration :15 The Nursing Process and Medication Administration Implementation 1. Maximizing therapeutic effect 2. Minimizing adverse effects provide comfort measures and help pt. cope with the therapeutic or adverse effects of a drug 3. Six rights of medication administration


The Nursing Process and Medication Administration :16 The Nursing Process and Medication Administration Evaluation Monitoring the patient’s response to drug therapy 1. Expected outcome 2. Unexpected outcome


The Five Rights of Medication Administration :17 The Five Rights of Medication Administration Right drug Right dose Right time Right route Right patient Medication errors are a major problem in health care today


Patient’s Rights :18 Patient’s Rights In addition to the 5 medication “rights”…… DO YOU THINK PATIENTS HAVE OTHER MEDICATION “RIGHTS”? What additional systems would you like to see in place to ensure safe drug administration?


“Right to”Constant System Analysis :19 “Right to”Constant System Analysis A “double-check” The entire “system” of medication administration Ordering, dispensing, preparing, administering, documenting Involves the physician, nurse, nursing unit, pharmacy department, and patient education


“Right to” :20 “Right to” Proper drug storage Proper documentation Accurate dosage calculation Accurate dosage preparation Careful checking of transcription of orders Patient safety


DRUG ORDERS :21 DRUG ORDERS Accurately written drug orders are part of patient rights


Six Elements of a Drug Order :22 Six Elements of a Drug Order 1. Name of the patient 2. Date order is written (start/ stop dates may be ordered) 3. Name of medication 4. Dosage includes size, frequency, and number of doses 5. Route of delivery 6. Signature of the prescriber


Drug Names :23 Drug Names Chemical name Describes the drug’s chemical composition and molecular structure Generic name (nonproprietary name) Name given by the United States Adopted Name Council Trade name (proprietary name) The drug has a registered trademark; use of the name restricted by the drug’s patent owner (usually the manufacturer)


Drug Names :24 Drug Names Chemical name propionic acid Generic name ibuprofen Trade name Motrin


Drug Evaluation Process :25 Drug Evaluation Process Chemicals which may have therapeutic value undergo a series of clinical studies to determine the therapeutic and toxic effects This is carefully controlled by the Food and Drug administration (FDA) The process can take 5-6 yrs or more


Pregnancy Categories :26 Pregnancy Categories All drugs are required by the FDA to be assigned to a pregnancy category of risk / safety A, B, C, D, X These categories indicate the actual or potential teratogenic effects on the fetus


Controlled Substances :27 Controlled Substances Drugs with abuse potential are classified by the FDA as controlled substances The Drug Enforcement Agency (DEA) enforces their control


Over-the-Counter Drugs :28 Over-the-Counter Drugs Available without a prescription Are deemed to be safe when used as directed Can cause interactions with prescription medications Are often considered by patients not to be “drugs”


:29 Introduction to Pharmacologic Principles Lecture 1 Part 2 This lecture is intended solely for the education of Grossmont College nursing students enrolled in Pharmacology 118. It may not be reproduced or distributed. PHARMACOLOGY118


Pharmacologic Principles :30 Pharmacologic Principles Drug Any chemical that affects the physiologic processes of a living organism Pharmacology The study or science of drugs


Pharmacologic Principles :31 Pharmacologic Principles Knowledge of pharmacologic principles: why a drug is ordered how to administer drugs assessment of therapeutic benefits how to deal with toxic adverse effects The nurse with a sound knowledge base in pharmacology is better equipped to implement the nursing process


Pharmacologic Principles :32 Pharmacologic Principles Pharmaceutics Pharmacokinetics Pharmacodynamics Pharmacotherapeutics Pharmacognosy Toxicology


Pharmacologic Principles :33 Pharmacologic Principles Pharmaceutics The study of various drug forms Deals with the delivery system IV, PO, IM Injection, capsule, timed-release, topical Determines the rate at which the drug will dissolve and be absorbed


Pharmacologic Principles :34 Pharmacologic Principles Pharmaceutics The pharmaceutical phase is concerned with the disintegration of the dosage form or dissolution of the drug in the body How the dosage forms affect the way the body metabolizes the drug and how the drug affects the body


Pharmacologic Principles :35 Pharmacologic Principles Pharmaceutics The dosage form determines the rate at which a drug enters the body A variety of dosage forms are available to increase the accuracy of dosing and to obtain therapeutic responses with the least amount of adverse effects


Pharmacologic Principles :36 Pharmacologic Principles Pharmaceutics Pharmacokinetics Pharmacodynamics Pharmacotherapeutics Pharmacognosy Toxicology


Pharmacologic Principles :37 Pharmacologic Principles 2) Pharmacokinetics The study of what actually happens to a drug from the time it enters the body until it has left the body a. Absorption movement of a drug from the site of administration b. Distribution transport of a drug in the bloodstream c. Metabolism alteration of a drug in the body d. Excretion elimination of the drug or its compound from the body


2) Pharmacokinetics :38 2) Pharmacokinetics a. Absorption The route of administration affects the rate and extent of absorption of that drug A. Enteral (GI tract) B. Parenteral C. Topical The extent of absorption is called BIOAVAILABILITY KEY POINT: not all drug formulations are equally absorbed


a. Absorption of oral drugs :39 a. Absorption of oral drugs Factors that affect absorption varies according to the dosage form and route Food or fluids administered with the drug help or hinder absorption food may delay transit to the intestines or, high fat foods may help some fat soluble drugs Dosage formulation tablets, capsules- some dissolve in the stomach, others in the intestine. Certain types are coated to disolve slowly and have timed release. Some types are formulated with small particles that dissolve super fast- ie: micronized glyburide


a. Absorption of oral drugs :40 a. Absorption of oral drugs Factors that affect absorption varies according to the dosage form and route Status of the absorptive surface portions of the small intestine may be missing or damaged Rate of blood flow to the small intestine blood flow may be decrease to the intestine in certain instances ie. sepsis, exercise, labor Acidity of the stomach food increases gastric acid production leading to decreased stomach PH. Drugs are formulated to dissolve at a specific PH level. Status of GI motility Fast or slow transit time due to pathology, conditions, or other medications change transit time


a. Absorption of oral drugs :41 a. Absorption of oral drugs Some drugs need to be taken on an empty stomach with a full glass of water Other drugs should be taken on a full stomach or with food to enhance absorption or minimize gastric irritation


a. Absorption of oral drugs :42 a. Absorption of oral drugs Drugs given by the oral route are absorbed into the mesenteric blood system and go to the liver for biotransformation before traveling on to the general systemic circulation. This is called the FIRST PASS EFFECT Therefore some of the drug is inactivated and not all will be available for use at its intended site of action. Drugs are formulated to account for this difference in availability to the tissues- called (bioavailability) This is why different forms of drugs are not equal ( see pg 18- Ch 2)


a. Absorption of parenteral drugs :43 a. Absorption of parenteral drugs Intravenous (fastest delivery into the blood circulation) Intramuscular Subcutaneous Intrathecal Intraarticular Intradermal Transdermal- can be considered parenteral too


a. Absorption of parenteral drugs :44 a. Absorption of parenteral drugs Parental drugs have no first pass effect Intravenous rapid and 100% bioavailable Avoids problems with stomach acid and intestinal absorption issues Intramuscular not as rapid as IV- will absorb better if there is a good blood supply Some IM medications are in DEPOT form- have a very slow absorption time (even months)- due to the formulation these drugs they should not be given IV- can cause an embolus


Absorption of topical drugs Avoids the first pass effect :45 Absorption of topical drugs Avoids the first pass effect Skin (including transdermal patches) Eyes Ears Nose Lungs (inhalation) Rectum- can have some first pass effect Vagina


a. Absorption of topical drugs :46 a. Absorption of topical drugs Many different formulations of topical drugs May be given for local or systemic effect All have different designs for absorption Gels and ointments- erratic absorption Lotions Patches- absorption at different rates Drops- eyes and ears Nasal sprays- Suppositories Inhalers


a. Absorption of oral drugs sublingual and buccal :47 a. Absorption of oral drugs sublingual and buccal Avoids the first pass effect Absorbed into the highly vascularized tissue under the tongue or between the cheek and the gum- the oral mucosa Bypass the liver Rapidly absorbed


a. Absorption :48 a. Absorption The ROUTE of administration affects the rate and extent of absorption of that drug


Pharmacologic Principles :49 Pharmacologic Principles 2) Pharmacokinetics The transport of a drug in the body by the bloodstream to its site of action a. Absorption b. Distribution c. Metabolism d. Excretion


b. Distribution :50 b. Distribution Drugs are distributed first to areas that have extensive blood supplies heart liver kidneys brain Areas of slower distribution are muscles skin fat Sites like bone and brain may be very difficult for drugs to reach due to either poor blood supply or barriers


b. Distribution of drugs :51 b. Distribution of drugs Factors that affect distribution Protein-binding Many drugs bind to proteins in the bloodstream -Albumin is the main protein to bind with drugs -Drugs bound to proteins are not available for use *called protein bound -Drugs not bound to protein are available to act at the intended site of action and exert their effects *called free drug Drug companies adjust drug dosages to allow for protein binding


b. Distribution of drugs :52 b. Distribution of drugs Factors that affect distribution If a patient has low albumin more free drug is available and the patient may have increased adverse effects (toxicity) If 2 drugs are given that are highly protein bound they compete for binding sites on the albumin. The drugs will have higher levels of “free” drug and the patient may have increased adverse effects Similar to musical chairs for binding sites


b. Distribution of drugs :53 b. Distribution of drugs Factors that affect distribution Water soluble Water soluble drugs tend to stay in the bloodstream and have slow absorption into the tissues. vs. fat soluble Fat soluble drugs are distributed to the tissues more quickly


b. Distribution of drugs :54 b. Distribution of drugs Factors that affect distribution Blood-brain barrier -network of capillaries that makes it more difficult for drugs to pass through--will allow some fat soluble drugs to pass through Placental barrier -in general whatever mom gets the fetus gets


Pharmacologic Principles :55 Pharmacologic Principles a. Absorption b. Distribution c. Metabolism d. Excretion


:56 Introduction to Pharmacologic Principles Lecture 1 Part 3 This lecture is intended solely for the education of Grossmont College nursing students enrolled in Pharmacology 118. It may not be reproduced or distributed. PHARMACOLOGY118


Pharmacologic Principles :57 Pharmacologic Principles 2) Pharmacokinetics a. Absorption b. Distribution c. Metabolism d. Excretion


c. Metabolism of drugs :58 c. Metabolism of drugs Also Known as Biotransformation A biochemical reaction involving a parent drug It takes place mainly in the liver and produces 1. An inactive metabolite 2. A more soluble compound 3. A more potent metabolite


c. Metabolism (biotransformation) :59 c. Metabolism (biotransformation) Organs or body tissues responsible for metabolism: Liver (mainly) Skeletal muscle Kidneys Lungs Plasma Intestinal mucosa


c. Metabolism (biotransformation) :60 c. Metabolism (biotransformation) Hepatic Cytochrome P-450 enzyme system These enzymes control a variety of biochemical reactions that aid in metabolism These enzymes are largely targeted against lipid-soluble and nonpolar (no charge) drugs which are difficult to eliminate These include the majority of medications


c. Metabolism (biotransformation) :61 c. Metabolism (biotransformation) The capability of the liver to metabolize drugs varies widely between patients Age Elderly have decreased hepatic enzymes Neonates have immature liver functions Genetics certain genetic groups metabolize drugs at different rates Foods Grapefruit and certain other foods Concurrent use of other medications Tylenol and many other drugs Diseases Cardiovascular or Renal dysfunction


c. Metabolism (biotransformation) :62 c. Metabolism (biotransformation) Factors that decrease (delay) metabolism Cardiovascular dysfunction Renal insufficiency Starvation Obstructive jaundice Slow acetylator Erythromycin or ketoconazole drug therapy


c. Metabolism (biotransformation) :63 c. Metabolism (biotransformation) Decreased drug metabolism results in: Accumulation of drugs Prolonged action of the drugs Possible toxic levels


c. Metabolism (biotransformation) :64 c. Metabolism (biotransformation) Factors that increase (stimulate) metabolism Fast acetylator Drugs that stimulate the formation of new enzymes Barbiturate therapy Rifampin therapy


3. Metabolism (biotransformation) :65 3. Metabolism (biotransformation) Increased drug metabolism results in: Drugs may leave the system more quickly Diminished pharmacologic effects


c. Metabolism (biotransformation) :66 c. Metabolism (biotransformation) FIRST PASS EFFECT The initial metabolism of a drug and its passage from the liver into the circulation – A drug given via the oral route may be extensively metabolized (inactivated or changed) by the liver before reaching the systemic circulation high first-pass effect Oral drugs ( because they go through the liver) may not be 100% available to reach the intended sites of action


3. Metabolism (biotransformation) :67 3. Metabolism (biotransformation) FIRST PASS EFFECT– routes of administration The same drug—given IV—initially bypasses the liver, getting to it’s intended site of action more quickly and preventing the first-pass effect from taking place. IV drugs are 100% available to the body (bioavailability)


3. Metabolism (biotransformation) :68 3. Metabolism (biotransformation) FIRST PASS EFFECT– routes of administration The first-pass effect is one reason why drug dosages and frequency of administration are different depending on the route of administration IV DOSE is not always equal to an ORAL DOSE


c. Metabolism (biotransformation) :69 c. Metabolism (biotransformation) Which labs will the nurse review if there is a concern about the patient’s ability to metabolize drugs??


Pharmacologic Principles :70 Pharmacologic Principles 2) Pharmacokinetics a. Absorption b. Distribution c. Metabolism d. Excretion


d. Excretion :71 d. Excretion The elimination of drugs from the body Kidneys (main organ) Whether the drug is an original compound (parent compound), an active or an inactive metabolite---- Liver Bowel Biliary excretion Enterohepatic recirculation


:72 The kidneys remove the drugs that are unbound (free) in the plasma Certain drugs (like highly protein bound drugs) can’t be excreted and are reabsorbed back into the system d. Excretion


d. Excretion :73 d. Excretion Patients with renal failure will not be able to excrete drugs efficiently Drug levels will increase Patients may experience more adverse effects and toxicity


More Pharmacologic Principles of Pharmacokinetics :74 More Pharmacologic Principles of Pharmacokinetics Onset, Peak, Duration and Trough Onset The time it takes for the drug to elicit a therapeutic response


Pharmacologic Principles Pharmacokinetics :75 Pharmacologic Principles Pharmacokinetics Onset, Peak, Duration and Trough Peak The time it takes for a drug to reach its maximum therapeutic response when is the peak effect- ( good time for a dressing change or other painful procedure)


Pharmacologic Principles Pharmacokinetics :76 Pharmacologic Principles Pharmacokinetics Onset, Peak, Duration and Trough Duration The time a drug concentration is sufficient to elicit a therapeutic response how long is it going to last- (anticipate the next dose)


Pharmacologic Principles Pharmacokinetics :77 Pharmacologic Principles Pharmacokinetics Onset, Peak, Duration and Trough Trough Lowest blood level of a drug


Pharmacologic Principles Pharmacokinetics :78 Pharmacologic Principles Pharmacokinetics Half-life How do pharmaceutical companies determine how often a drug needs to be given to remain in a therapeutic range?


Pharmacologic Principles Pharmacokinetics :79 Pharmacologic Principles Pharmacokinetics Half-life The time it takes for one half of the original amount of a drug in the body to be removed A measure of the rate at which drugs are removed from the body Most drugs are considered to be effectively removed after about five half-lives**


Pharmacologic Principles Pharmacokinetics :80 Pharmacologic Principles Pharmacokinetics Some drugs are eliminated quickly and need to be given frequently in order to remain in a therapeutic range Other drugs have extremely long half lives and remain in the body for a very long time


Pharmacologic Principles Pharmacokinetics :81 Pharmacologic Principles Pharmacokinetics Short ½ life– need to take frequently compliance may be a problem example: acyclovir 5 times daily Long ½ life- pt has an adverse reaction the drug will be in the body for hours or days example: Cialis T1/2 = 17 hours (Viagra might have been a better choice for this pt with a T1/2 of 4 hours)


Pharmacologic Principles Pharmacokinetics :82 Pharmacologic Principles Pharmacokinetics Steady state Where the amount of drug excreted is equal to the amount of drug absorbed with each dose Drugs accumulate until they reach a steady state - requires proper dose and timing - efficient metabolism and excretion Giving more drug could cause toxicity Giving less drug would not be therapeutic Typically occurs after 4-5 half-lives of administration


Pharmacologic Principles of Pharmacokinetics :83 Pharmacologic Principles of Pharmacokinetics Steady state Drugs with a very long half-life make take a longer time to reach a steady state - some antidepressants With certain drugs, to reach a steady state more quickly, a LOADING DOSE may be ordered This is a higher initial dose


:84 Introduction to Pharmacologic Principles Lecture 1 Part 4 This lecture is intended solely for the education of Grossmont College nursing students enrolled in Pharmacology 118. It may not be reproduced or distributed. PHARMACOLOGY118


Pharmacologic Principles :85 Pharmacologic Principles Pharmaceutics Pharmacokinetics Pharmacodynamics Pharmacotherapeutics Pharmacognosy


Pharmacologic Principles :86 Pharmacologic Principles 3) Pharmacodynamics The mechanism of drug actions in living tissues How drugs alter a system


Pharmacodynamics :87 Pharmacodynamics A positive change in a physiologic system is called a THERAPEUTIC EFFECT This is the goal of drug therapy


Pharmacodynamics :88 Pharmacodynamics Drugs exert their action on cells in 3 ways: Receptor interactions Enzyme interactions Nonspecific interactions


Pharmacodynamics :89 Pharmacodynamics a) Receptor interactions Key in a lock Drug binds to a specific site on the cell (called a receptor site) and modifies the function of the cell This is the way many drugs work How strong a drug binds to the receptor site is called the AFFINITY for that binding site


Pharmacodynamics :90 Pharmacodynamics a) Receptor interactions AGONISTS Drugs that fit well at the receptor site and elicit their own response ANTAGONISTS Drugs that attach to the receptor site and block other drugs from attaching


Pharmacodynamics :91 Pharmacodynamics a) Receptor interactions Both Agonists and Antagonists are used in drug therapy Albuterol inhaler- for asthma is an example of an agonist medicine Benadryl ( diphenhydramine) is an antagonist.


Pharmacodynamics :92 Pharmacodynamics b) Enzyme interactions The drug alters the enzymes necessary for a certain body function The Ace Inhibitor class of blood pressure medicines are an example of drugs that exert their action by altering enzyme pathways


Pharmacodynamics :93 Pharmacodynamics c) Non-specific interactions alter the cell structure alter some crucial cell process Antibiotics are an example of drugs that alter the cell wall or alter the internal function of the bacterial cell


Pharmacodynamics :94 Pharmacodynamics Once the drug is at the site of action, it can modify the rate (increase or decrease) at which the cells or tissues function A drug cannot make a cell or tissue perform a function it was not designed to perform


Pharmacologic Principles :95 Pharmacologic Principles Pharmaceutics Pharmacokinetics Pharmacodynamics Pharmacotherapeutics Pharmacognosy Toxicology


Pharmacologic Principles :96 Pharmacologic Principles 4) Pharmacotherapeutics The use of drugs and the clinical indications for drugs to prevent and treat diseases


Pharmacotherapeutics :97 Pharmacotherapeutics Acute therapy-------- stroke, heart attack Maintenance therapy--- hypertension, hyperlipidemia, Supplemental/replacement therapy----insulin, iron, thyroid Palliative therapy--- high dose opioids for cancer patients, Supportive therapy—fluid and electrolytes, volume expanders Prophylactic therapy--- antibibiotics before surgery Empiric therapy– experience shows it works- no evidence-


Pharmacotherapeutics :98 Pharmacotherapeutics Therapeutic Drug Monitoring Certain drugs need close monitoring of blood levels during administration They have a potential to become toxic-- some can become toxic at very low blood levels


Pharmacotherapeutics :99 Pharmacotherapeutics Therapeutic Drug Monitoring The goal is to have enough drug in the body to get the positive desired effect--without producing undesirable adverse effects or toxicity. If the peak is too high, organ damage may result. If the trough is too low, the drug may not be at therapeutic levels Some drugs have a very narrow range between therapeutic and toxic Digoxin (heart med) and Gentamycin (antibiotic) are examples of drugs commonly monitored with blood levels


Pharmacotherapeutics :100 Therapeutic Drug Monitoring Peak Level Highest blood level Trough Level Lowest blood level Blood is drawn at specfic times before and after drug administration--- the amount of the drug in the body guides the pharmacist in adjustment of drug dosages Pharmacotherapeutics


Pharmacotherapeutics :101 Pharmacotherapeutics Monitoring The effectiveness of drug therapy must be evaluated Intended therapeutic action (beneficial) Unintended but potential adverse effects (predictable, adverse reactions)


Pharmacotherapeutics :102 Pharmacotherapeutics Monitoring Therapeutic index Drug concentration Patient’s condition Tolerance and dependence Interactions Adverse drug effects


Pharmacotherapeutics :103 Pharmacotherapeutics MONITORING Therapeutic index Ratio of safety: the range between a drug’s therapeutic & toxic effects– a LOW therapeutic index means the drug has a greater chance of causing an adverse reaction Drug concentration Drug levels may become toxic if increased i.e.: renal/hepatic patients whose normal mechanisms for metabolism and excretion are compromised Patient’s condition Diseases and and other conditions such as stress and anxiety are just a few examples of conditons that can alter a patient’s response to drug therapy


Pharmacotherapeutics :104 Pharmacotherapeutics MONITORING Tolerance a decreasing response to repeated doses Dependence a physiological or psychological need for a drug


Pharmacotherapeutics :105 Pharmacotherapeutics Monitoring Interactions The alteration of the action of a drug by other substances may occur with other drugs or food Other prescribed drugs Over-the-counter medications- Herbal therapies Certain foods Important to get a good nursing history of all drugs, herbs and problem foods that patient is taking Older patients are typically on multiple medications that may interact--- “polypharmacy”


Pharmacotherapeutics :106 Pharmacotherapeutics Monitoring Interactions Drug interaction issues Additive effect--smaller doses can be given with same effect ie. Tylenol and Codeine Synergistic effect—2 drugs have a greater effect than either drug alone-- HCTZ with enalapril Antagonistic effect--2 drugs have less of an effect than with either drug alone-- antacids with tetracycline- Incompatibility—2 drugs mixed together and one or more deteriorates---furosemide and heparin


Pharmacotherapeutics :107 Pharmacotherapeutics Monitoring Interactions Incompatibility- can be oral or IV drugs Focus for nurses when giving different IV drugs together Drugs may precipitate, become hazy, or change color when they are incompatible in the same IV tubing


Pharmacotherapeutics :108 Pharmacotherapeutics Monitoring Adverse Drug Events Potential hazards of medication use can be mild and minor can be life- threatening Two broad categories 1. Medication errors 2. Adverse drug reactions


Pharmacotherapeutics :109 Pharmacotherapeutics Monitoring Adverse Drug Events 1. Medication errors Big focus in all health care areas today Can occur anywhere along the chain- prescriber, pharmacist, nurse, technician Medication errors are PREVENTABLE


Pharmacotherapeutics :110 Pharmacotherapeutics Adverse drug reactions Any reaction to a drug that is unexpected and undesirable that occurs at therapeutic doses 1. Hypersensitivity (allergic) reaction 2. Pharmacologic reactions Predictable, well-known reactions that result in little or no change in patient management -Predictable frequency Usually resolve when the drug is discontinued


Pharmacotherapeutics :111 Pharmacotherapeutics Contraindications to therapy Any characteristic of the patient, especially a disease state, that makes the use of a given medication dangerous for the patient It is important to assess for contraindications!


Pharmacotherapeutics :112 Pharmacotherapeutics Contraindications to therapy When the drug will be dangerous for the pt. Allergic to drug Pregnant Impaired liver or kidney function Wrong drug for the problem Many others


Pharmacologic Principles :113 Pharmacologic Principles 5) Pharmacognosy The study of natural (plant and animal) drug sources


Pharmacologic Principles :114 Pharmacologic Principles 5) Pharmacognosy Four main sources for drugs Plants Animals Minerals Laboratory synthesis


Pharmacologic Principles :115 Pharmacologic Principles 5) Pharmacognosy The source of all early drugs was from nature Foxglove--cardiac drugs Insulin– pigs and beef aluminum hydroxide Most new drugs are created synthetically in the lab can be mass produced We continue to discover many natural sources for drugs


Pharmacologic Principles :116 Pharmacologic Principles 6) Toxicology The study of poisons and unwanted responses to drugs and other chemicals


Toxicology :117 Toxicology Drug Related Effects Teratogenic drugs or chemicals that result fetal defects Accutane Mutagenic drugs or chemicals that cause permanent changes in the genetic composition may pose a genotoxic hazard to hospital personnel or family members caring for the patient. Carcinogenic drugs, chemicals etc. that cause cancer Tobacco Tamoxifen


Toxicology :118 Toxicology http://toxicology.ucsd.edu/modules.htm California Teratogen Information Service & Clinical Research Program(800) 532-3749 (CA only), UCSD Medical Center , Department of Pediatrics