Pharmacology-Prelim-Reviewer PDF

Summary

This document provides an overview of fundamental concepts in pharmacology, including the history of drugs and their effects on the body. It details the unique role of nurses in drug therapy, emphasizing aspects such as administration, assessment, and patient teaching.

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FUNDAMENTAL CONCEPT OF NURSING  19TH CENTURY — Morphine & codeine PHARMACOLOGY (MODULE 1) extract from opium. Introduction of atropine & iodine  EARL...

FUNDAMENTAL CONCEPT OF NURSING  19TH CENTURY — Morphine & codeine PHARMACOLOGY (MODULE 1) extract from opium. Introduction of atropine & iodine  EARLY 20TH CENTURY — Aspirin from INTRODUCTION TO DRUGS salicylic acid. Introduction of  The human body works through a Phenobarbital, insulin, sulfonamides complicated series of chemical reactions  1940 — Discovery antibiotics (penicilline, and processes. tetracycline, streptomycin),  Drugs are chemicals that are introduce antihistamines, cortisone into the body to cause some sort of  1950 — Discovery antipsychotic drug, change. antihypertensives, oral contraceptives,  Drugs will undergo process with in the polio vaccine body which involve breaking and eliminating the drugs, in turn affect the body's complex series of chemical PHARMACOLOGY reactions.  Is the study of drugs including their  Understanding how drugs act on the origins, history, uses, and properties. A body to cause changes and applying that drug is defined a substance that is used knowledge in the clinical setting are to treat, cure or prevent a disease or important aspects of nursing practice. otherwise enhance physical or mental health.  Is the study of the biological effects of THE NURSE IS IN A UNIQUE POSITION chemicals. REGARDING DRUG THERAPY BECAUSE NURSING RESPONSIBILITIES INCLUDE  It is the scientific study of the origin, THE FOLLOWING: nature, chemistry, effects and uses of drugs.  Administering drugs  In clinical practice, health care providers  Assessing drug effects focus on how chemicals act on living  Intervening to make the drug organisms. regimen more tolerable  Greek word pharmakon=  Providing patient teaching about "drugs/medicine " + logos = "science" drugs and drug regimen.  deals with the study of drugs and their  Monitoring the overall patient care actions on living organisms. plan to prevent medication error  Drugs: from Dutch droog= "dry".  Knowing how drugs works make Chemical substance that have an effect these tasks easier to handle, thus on living organisms. enhancing drug therapy.  Therapeutic drugs, which are often called Medicines, are those drugs that are used for the prevention or treatment HISTORY OF DRUGS of diseases.  EARLY DRUGS — Plants, animals & Diseases that cause illnesses may be treated minerals in several different ways, which are referred to as therapies. The various approaches to  1550 BC — Egyptians created Ebers therapy are called Therapeutic Methods. Medical Papyrus THERAPEUTIC METHODS:  2700 BC — Earliest recorded drug use found in Middle East & China  131-201 AD — Galen a Roman physician;  DRUG THERAPY — treatment with initiated common use of prescriptions drugs  1240 AD — Introduction of apothecary  DIET THERAPY — treatment with diet. (pharmacy) system (Arab doctors)  PHYSIOTHERAPY — treatment with  15TH CENTURY— Apothecary shops natural, physical forces. owned by barber surgeons, physicians, Independent merchants  PSYCHOLOGICAL THERAPY — identification of stressors and methods  18TH CENTURY — Small pox vaccine that can be used to reduce/eliminate (by Edward Jenner, British Doctor) stress. — CHANG All drugs have several names, which may  ILLEGAL DRUGS — sometimes referred cause confusion. When administering the to as recreational drugs. These are prescribed drug, the spelling on the drug drugs or chemical substances that are package must correspond exactly with the used for non-therapeutic purposes. spelling of the drug ordered to ensure that the Obtained illegally or have not received proper medicine is administered. approval for use by the FDA. Ex. Ecstacy, Marijuana DRUG NAMES SOURCES OF DRUG STANDARDS AND DRUG INFORMATION 1. CHEMICAL NAME — Most  Drug products made by different meaningful to the chemist. (Example: 4-thia- manufacturers or in different batches by 1-azabicycloheptane-2carboxylic acid, 6- the same manufacturer must be aminophenylacetyl}amino)-3,3-dimethyl-7 uniformly pure and potent. oxo-)  The USP/N (united states pharmacopeia/ 2. GENERIC NAME — Before a drug national formulary- provide standards for becomes official, it is given a generic name or the identity, quality, strength and purity of common name. It is simplier than the substance used in the practice of health chemical name. (Example: Amoxicillin) care. 3. BRAND NAME — (trademark) is  The standards described in the USP/NF followed by symbol ®_ This symbol indicates are enforced by the FDA as the official that the name is registered and that the use standards for the manufacture and of the name is restricted to the owner of the quality control of medicines and drug, which is usually the manufacturer. nutritional supplements produce in the (Example: Amoxil Forte) united states.  In the Philippines, The Food and Drug Example: Administration (FDA), as the regulatory authority of the Philippines responsible Chemical name: 4-thia-1-azabicycloheptane- for all matters pertaining to drug products, 2carboxylicacid, 6-aminophenylacetyl}amino)- has issued several guidelines to ensure 3,3- dimethyl-7oxo- that drug establishments provide the most accurate information relating to Generic Name: ampicillin their product. Brand Name: Principen, Polycillin SUBDIVISION OF PHARMACOLOGY — Drugs may be classified by a variety of methods according to:  PHARMACODYNAMICS — Study of the  Body System they affect e.g biochemical & physiological effects of  The Central Nervous System, drugs & mechanisms of action what the drug does to the body  Cardiovascular System  Therapeutic use or Clinical Indication  PHARMACOKINETICS — Deals with the  Physiologic or chemical action absorption, distribution, biotransformation & excretion of drugs what the body does to the drug. Deals with beneficial effects — Drugs may be further classified as of the drugs (medicines) Prescription and NonPrescription Drugs.  PHARMACOTHERAPEUTIC/ CLINICAL  PRESCRIPTION DRUGS — require an PHARMACOLOGY — The clinical order by a health professional who is purpose or indication for giving a drug. licensed to prescribe drugs such as The branch of pharmacology that uses physician, nurse practitioner (in US or drugs to treat, prevent and diagnose any other countries), a physician disease" assistant, pharmacist, or a dentist.  PHARMACOGNOSY — The study of  NONPRESCRIPTION DRUGS (OVER medicines or crude drugs produced from THE COUNTER DRUGS/OTC) — are natural sources such as plants, microbes, sold without prescription in pharmacy or and animals. It includes analysis of their in the health section department or biological, chemical, biochemical, and grocery stores. physical properties. — CHANG  TOXICOLOGY — Study of biologic  DRUG ALLERGY toxins: study of poison & its effects deals with deleterious effects of physical &  The immunologic reaction to the chemical agents (including drugs) in drug. human  ANAPHYLACTIC REACTION  PHARMACOTHERAPY — It is the use  Anaphylactic Reaction of drugs to prevent, diagnose, or treat signs, symptoms and disease process.  A severe allergic reaction which usually occurs immediately following  PHARMACODYNAMICS — What the administration of the drug. drugs does to the body.  PHARMACOKINETICS — What the body does to the drugs.  DRUG TOLERANCE  A decreased physiologic response to the repeated administration of a drug Nurses deal with Pharmacotherapeutics, or or chemically related substance. Clinical Pharmacology, the branch of pharmacology that uses drugs to treat,  Excessive increase in the dosage is prevent, and diagnose diseases. required in order to maintain the desired therapeutic effect. CLINICAL PHARMACOLOGY : Addresses two key concerns  DRUG INTERACTION — Effects of one drug are modified by the prior or 1. The drug's effects on the body concurrent administration of another drug, 2. The body's response to the drug thereby increases or decreases the pharmacological action.  DRUG ANTAGONISM — The EFFECTS OF THE DRUGS conjoint effects of two drugs is less than the drugs acting separately.  SUMMATION — The combined  THERAPEUTIC EFFECT effect of two drugs produces a result  The primary effect intended, that is that equals the sum of the individual the reason the drug is prescribed. effect of each agent.  Also called desired effect.  SYNERGISM — The combined effects of drugs is greater than the sum of each individual agent acting independently.  SIDE EFFECT AND ADVERSE EFFECT  POTENTIATION — The concurrent  The effect of the drug that is not administration of two drugs in which intended. one increases the effect of the other  Are not the desired therapeutic drug. effects; may be unpleasant or even dangerous. THERAPEUTIC EFFECTS OF DRUG  PALLIATIVE — Relieves the symptoms of a disease but not affect the disease itself. ….. Ex. Analgesic for pain  CURATIVE — Treats the disease condition Ex. Antibiotic for infection  SUPPORTIVE — Sustains body functions until other treatment of the body's response can take over. Ex. Mannitol to reduce/CP in a client for surgery due to brain tumor. — CHANG  SUBSTITUTIVE — Replaces body fluids  The ratio of the dose that produces or substances. Ex. insulin injection for toxicity to the dose that produces a diabetes mellitus clinically desired or effective response  TD50 = the dose of drug that causes a toxic response in 50% of the population  CHEMOTHERAPEUTIC — Destroys malignant cells. Ex. Cyclophophamide for  ED50 = the dose of drug that is cancer of the prostate gland. therapeutically effective in 50% of the population  RESTORATIVE — Returns the body to health. PHARMACODYNAMICS (MODULE 2)  The study of the interactions between the chemical components of living systems and the foreign chemicals, including drugs, that enter living organisms(the way a drug affects a body).  The study of the interactions between drugs and their receptors and the series of events that result in a pharmacologic response.  For example, diphenhydramine (Benadryl) is an antihistamine. Its primary effect is to treat symptoms of allergies. Its secondary effect is to depress the central nervous system causing drowsiness. The secondary effect is desirable if the patient needs bedrest, but undesirable if the patient is driving a car. THESE ARE DESIGNED TO:  When a new chemical enters the system, multiple changes in and interferences  Ascertain whether the new drug has any with cell functioning may occur. To avoid harmful or beneficial effects on vital such problems, drug development works organ, function, including cardiovascular, to provide the most effective and least renal, and respiratory function. toxic chemicals for therapeutic use.  Elucidate the drug's mechanisms and therapeutic effects on target organs. Drugs usually work in one of four ways:  Determine the drug's pharmacokinetic properties thereby providing some 1. To replace or act as substitute for indication of how the drug would be missing chemicals handled by the human body. Although 2. To increase or stimulate certain few people object to using animals, there cellular activities are even fewer willing to refuse all medical treatment and pharmacotherapy 3. To depress or slow cellular activities that result from animal testing. 4. To interfere with the functioning of foreign cells, such as invading microorganisms or neoplasms THERAPEUITC DRUG MONITORING leading to cell death(drugs that act in  Therapeutic window (TW) is the range of this way are called drug concentrations in which a drug is CHEMOTHERAPEUTIC AGENTS effective DRUG SAFETY- THERAPEUTIC INDEX  Measurement of drug safety, refers to the relationship between toxic and therapeutic dosing  TI= TD50/ED50 — CHANG GRADED DOSE RESPONSE  POTENCY — Is characterized of RELATIONSHIP AND THERAPEUTIC drug action useful for comparing RESPONSE different pharmacologic agent  The dose-response relationship is a  EFFICACY — The ability of a drug to central concept in toxicology. initiate a cellular effect  It is a framework around which all hazard assessment testing is performed and dose-response model extrapolations are  QUANTAL DOSE - RESPONSE based and from which environmental RELATIONSHIP regulations are derived.  Another important dose-response  In the area of toxicological mechanism relationship is that between the dose research, such investigations are also of the drug and the proportion of a focused on attempting to clarify the population of patients that responds underlying basis for dose-dependent to it. transitions.  Thus, the dose-response relationship provides the principal focus about which and from which toxicological research and applications emerge.  Based on the central role that the dose- response relationship has in the discipline of toxicology, it is not surprising that their history is inseparable.  The pharmacological effect of a drug depends on its concentration at the site of action, which, in turn, is determined by the dose of the drug administered. Such a relationship is called dose-response relationship —— A therapeutic response is a consequence of a medical treatment of any  Two important drug characteristics, kind, the results of which are judged to be potency and efficacy, can be determined desirable and beneficial. This is true whether by graded dose-response curves. the result was expected, unexpected, or even an unintended consequence of the treatment. 1. POTENCY — The amount of a drug required to produce a desired response is called the potency of the drug. AGONISTS AND ANTAGONISTS 2. EFFICACY — Efficacy is the magnitude of response a drug  AGONISTS — Drugs that occupy causes when it interacts with a receptors and activate them. receptor.  ANTAGONISTS — Drugs that occupy receptors but do not activate them.  A graded dose-response curve is one Antagonists block receptor activation by that has the general shape of a agonists. rectangular hyperbola where two important drug properties can be determined: —— The main difference between an agonist and antagonist is that they have opposite actions. An agonist drug always produces a specific action and triggers the receptor to produce a natural response. On the other hand, antagonist drugs block or oppose the natural action or response of a receptor. — CHANG CELLULAR RECEPTORS AND DRUG  G-PROTEIN - COUPLED RECEPTORS ACTION  G-protein-coupled receptors bind a  Cellular receptors are proteins either ligand and activate a membrane protein inside a cell or on its surface that receive called a G-protein. a signal. This is a chemical signal in normal physiology where a protein ligand  The activated G-protein then interacts binds a protein receptor. The ligand is a with either an ion channel or an enzyme chemical messenger released by 1 cell to in the membrane. Before the ligand binds, signal itself or a different cell. the inactive G-protein can bind to a site on a specific receptor.  Once the G-protein binds to the receptor, the G-protein changes shape, becomes active, and splits into two different subunits. One or both of these subunits may be able to activate other proteins as a result. DIFFERENT TYPES OF CELLULAR RECEPTORS 1. Ion channel receptors 2. G-protein coupled receptors (GPCRs) 3. Enzyme-linked receptors  ION CHANNEL - LINKED RECEPTORS  Ion channel-linked receptors bind a ligand and open a channel through the membrane that allows specific ions to  ENZYME - LINKED RECEPTORS pass through.  Enzyme-linked receptors are cell-surface  To form a channel, this type of cell- receptors with intracellular domains that surface receptor has an extensive are associated with an enzyme. In some membrane-spanning region. cases, the intracellular domain of the  When a ligand binds to the extracellular receptor itself is an enzyme. region of the channel, there is a  Other enzyme-linked receptors have a conformational change in the proteins small intracellular domain that interacts structure that allows ions such as sodium, directly with an enzyme. When a ligand calcium, magnesium, and hydrogen to binds to the extracellular domain, a pass through. signal is transferred through the membrane, activating the enzyme.  Activation of the enzyme sets off a chain of events within the cell that eventually leads to a response. — CHANG DRUG ACTION DRUG BLOOD LEVEL  All drug actions have an onset, peak and  When a drug is circulating in the blood, a duration of action. blood sample may be drawn and assayed to determine the amount of drug present.  THE ONSET OF ACTION — Is when the  It is important for certain drugs (e.g. concentration of a drug at the site of anticonvulsants, aminoglycoside action is sufficient to start a physiologic antibiotics) to be measures to ensure that (pharmacologic) response. Many factors the drug blood level is within the such as the route of administration, and therapeutic range. binding to receptor sites, affect the onset of action. In general, increasing the dose ADVERSE EFFECTS OF DRUGS of the drug hastens the onset of action by shortening the time required to achieve  No drug has a single action. When a the necessary concentration of drug at drug enters a patient and is then the target site. absorbed and distributed, the DESIRED ACTION (i.e the expected response) usually occurs. However, all drugs have the potential to affect more than one  PEAK ACTION — Is the time at which body system simultaneously, thereby the drug reaches the highest producing responses that are known as concentrations on the target receptor SIDE EFFECTS or COMMON ADVERSE sites, thereby inducing the maximal EFFECTS, which are MILD or SERIOUS pharmacologic response for the dose ADVERSE EFFECT, which can lead to given. toxicity.  IDIOSYNCRATIC REACTION  DURATION OF ACTION — Is how long  When something unusual or abnormal the drug has a pharmacologic effect. The happens when a drug is first onset, peak, and gyration of action of a administered. The patient usually drug are often illustrated by a me - demonstrates an unexpectedly strong response curve, which is also known as response to the action of the drug. a drug concentration profile.  Generally the result of a patients inability to metabolize a drug because of genetic  A time — response curve demonstrates deficiency of certain enzymes. the relationship between the  This type of reaction is RARE. administration of a drug and the associated response.  ALLERGIC REACTIONS  If the drug level does not reach the  Or HYPERSENSITIVITY REACTION, minimum effective concentration, there occurs among patients who have will be no pharmacologic effect. previously been exposed to a drug and whose immune system have developed  If the peak level exceeds the toxicity antibodies to the drug. threshold, toxic effects will result.  These reaction is most commonly seen  Generally, the drug concentration is as raised irregularly shaped patches on targeted to be the middle of this range, the skin known as hives which cause between the minimum effective response severe itching (urticaria) and the toxic response, this is referred to as THERAPEUTIC RANGE  ANAPHYLACTIC REACTION — severe life threatening reaction that causes respiratory distress and cardiovascular collapse. DRUG INTERACTIONS  Is said to occur when the action of one drug is altered or changed by the action of another drug. Drug interactions are elicited in two ways: 1. By agents that, when combined, increase the effectiveness of one or both drugs. 2. By agents that, when combined, decrease the effectiveness of one or both drugs. — CHANG 3. DISTRIBUTION — drug refers to the process of a drug leaving the bloodstream and going into the organs and tissue. 4. ELIMINATION — the drug from a blood relies on two process: BIOTRANSFORMATION and EXCRETION. DRUG ABSORPTION  This refers to the passage of drug molecules from the site administration PHARMACOKINETICS (MODULE 3) into the circulation.  The process of drug absorption applies to all routes of administration, except for  How the body acts on the drug the TOPICAL ROUTE and INTRAVENOUS ADMINISTRATION.  Involves the study of absorption, distribution, metabolism(biotransformation), and excretion of drugs. Routes of Drug administration  ENTERAL ROUTE — the drug is administered directly into the Gl tract CRITICAL CONCENTRATION — The amount of a drug that is needed to cause a  PARENTAL ROUTE — bypasses the GI therapeutic effect effect. tract with the use of subcutaneous, Intramuscular and intravenous injection. LOADING DOSE — a higher dose than that usually used for treatment) reach the critical  PERCUTANEOUS ROUTE — involves concentration. drugs being absorbed thru the skin and mucus membranes. DYNAMIC EQUILIBRIUM ROUTE FACTORS AFFECTING  The actual concentration that a drug ABSORPTION reaches in the body results from a dynamic equilibrium involving the rate of Intravenous None: direct entry into the venous several processes: system  Absorption from the site of entry Intramuscular  Perfusion or blood flow to the muscle  Distribution to the active site  Fat content of the muscle  Biotransformation (metabolism) in the liver  Temperature of the muscle: cold causes vasoconstriction and  Excretion from the body decreases absorption; heat causes vasodilation and increases absorption This study of drugs disposition in the body Subcutaneous  Perfusion or blood flow to the and focuses on the changes in drug plasma tissue concentration.  Fat content of the tissue  Temperature of the tissue: cold 1. LIBERATION — is the process in which causes vasoconstriction and a pharmaceutical substance is released decreases absorption; heat from the formulation it is delivered in. It is causes vasodilation and the first step in the process by which increases absorption medication enters the body and liberates the active ingredient that has bee PO (oral)  Acidity of stomach administered.  Length of time in stomach 2. ABSORPTION — drug refers to the movement of drug into the bloodstream,  Blood flow to gastrointestinal with the rate dependent on the physical tract characteristics of the drug and its  Presence of interacting foods or formulation. drugs — CHANG  Carriers may be inhibited by compounds that compete for the same carrier PR (rectal)  Perfusion or blood flow to the rectum  Lesions in the rectum C. ACTIVE TRANSPORT  Length of time  This mode of drug entry also involves retained for specific carrier proteins absorption  Active transport is energy-dependent and Mucous  Perfusion or blood is driven by the hydrolysis of Membranes flow to the area AdenosineTri-phosphate (ATP) into (sublingual, Integrity of the Adenosine Di-phosphate (ADP) buccal) mucous membranes  It is capable of moving drugs against a  Presence of food or concentration gradient (from a region of smoking low drug concentration to one of higher drug concentration)  Length of time retained in area  Carriers may be inhibited by compounds that compete for the same carrier Topical (skin)  Perfusion or blood flow to the area  Integrity of skin D. ENDOCYTOSIS & EXOCYTOSIS Inhalation  Perfusion or blood  This type of drug delivery transports flow to the area drugs of extra large size across the cell membrane  Integrity of lung lining  Endocytosis involves engulfment of a  Ability to administer drug molecule by the cell membrane and drug properly transport into the cell by squeezing the drug-filled vesicle  Exocytosis is the reverse of endocytosis and is used by cells to secrete many I.DRUG ABSORPTION MECHANISMS substances by a similar vesicle formation process  Certain neurotransmitters (for example, A. PASSIVE DIFFUSION norepinephrine) are stored in membrane- bound vesicles in the nerve terminal and  Majority of drugs are absorbed through are released by exocytosis this mechanism  The driving force for passive absorption of a drug is the concentration gradient II. FACTORS INFLUENCING DRUG (drug moves from a region of high ABSORPTION concentration to one of lower concentration)  Passive diffusion does not involve a 1. EFFECT OF pH ON DRUG carrier and does not require energy ABSORPTION  Lipid-soluble drugs readily move across  Most drugs are either weak acids or most biologic membranes due to their weak bases solubility in the membrane bi-layers Acidic drugs are present in two forms;   Water-soluble drugs penetrate the cell The un-ionized form (HA) or an ionized membrane through aqueous channels or (charged) form (A-) [HA < → H++ A- ] pores Weak basic drugs are present in two  forms; The un-ionized form (B) or an ionized (charged) form (BH+) [BH+ < → B. FACILITATED DIFFUSION B + Ht]  Drug enter cell through specialized  A drug passes through membranes more transmembrane carrier proteins that readily if it is Un-ionized (uncharged or facilitate the passage of large molecules Non polar)  Drug moves from an area of high  N.B: concentration to an area of low concentration Acidic drugs are unionized in acidic medium; that's why acidic drugs are  This type of diffusion does not require absorbed from the stomach (PH: 1.5 energy to 3.5) — CHANG While Bases are present in their Factors Affecting Distribution unionized form in basic medium; that's why basic drugs are mainly absorbed from the Intestine (PH: 6-  ORGAN BLOOD FLOW — The rate at 7.4) which a drug is distributed to various organs after a drug dose is administered depends largely on the proportion of 2. BLOOD FLOW TO THE ABSORPTION cardiac output received by the organs. SITE  Highly Perfused Tissues: Brain,  Because blood flow to the intestine is Heart, Liver, and Kidneys much greater than the flow to the stomach, absorption from the intestine is  Less Perfused Tissues: Skeletal favored over that from the stomach muscle  Lowers Perfused Tissue: Skin, Bone and Adipose Tissue 3. TOTAL SURFACE AREA AVAILABLE FOR ABSORPTION EXAMPLE: Tissue perfusion is a factor in treating a patient with diabetes who has a  With a surface rich in brush borders lower-leg infection and needs antibiotics to containing microvilli, the intestine has a destroy the bacteria in the area. In this case, surface area about 1000-fold that of the systemic drugs may not be effective because stomach, making absorption of the drug part of the disease process involves changes across the intestine more efficient in the vasculature and decreased blood flow to some areas, particularly the lower limbs. If there is not adequate blood flow to the area, 4. CONTACT TIME AT THE ABSORPTION little antibiotic can be delivered to the tissues, SURFACE and little antibiotic effect will be seen.  If a drug moves through the GI tract very quickly, as can happen with severe  PLASMA PROTEIN BINDING — This is diarrhea, it is not well absorbed a saturable, and a drug can be displaced  Conversely, anything that delays the from binding sites by other drugs that transport of the drug from the stomach to have high affinity for such sites. The the intestine delays the rate of absorption acidic drugs bind to albumin and basic of the drug drugs to glycoprotein and Is-globulins.  Parasympathetic input (at rest) increases the rate of gastric emptying, while  BLOOD-BRAIN BARRIER — The blood- sympathetic input (stress) delays gastric brain barrier is a protective system of emptying cellular activity that keeps many things  Also, the presence of food in the (e.g., foreign invaders, poisons) away stomach both dilutes the drug and slows from the CNS. gastric emptying. Therefore, a drug taken  Drugs that are highly lipid-soluble with a meal is generally absorbed more are more likely to pass through the slowly blood-brain barrier and reach the CNS. Drugs that are not lipid-soluble are not able to pass the blood-brain DRUG DISTRIBUTION barrier.  Distribution involves the movement of a drug to the body's tissues.  PLACENTA AND BREAST MILK —  Drug are distributed to organs and Many drugs readily pass through the tissues via the circulation, diffusing into placenta and affect the developing fetus interstitial fluid cells from the circulation. in pregnant women. Many other drugs are secreted into breast milk and  Example: Some drugs are actively therefore have the potential to affect the transported into cells, where they may neonate. undergo enzymatic biotransformation.  Two types of BIOTRANSFORMATION. DEFINITIONS OF TERMS 1. Enzymatic Biotransformation 2. Non-enzymatic Biotransformation METABOLISM — is an essential pharmacokinetic process, which render lipid soluble and non polar compounds to water soluble and polar compounds so that they are excreted various process from the body. — CHANG BIOTRANSFORMATION —It is a specific ENZYME INDUCTION term used for the chemical transformation of xenobiotics in the living organisms. — The presence of a chemical that is metabolized by a particular enzyme system often increases the activity of that enzyme system. XENOBIOTICS — These are all chemical substances that are not nutrient for the body — Some drugs cannot be taken together (foreign Body) and which enter the body effectively. The presence of one drug speeds through ingestion, inhalation or dermal the metabolism of others, preventing them exposure. from reaching their therapeutic levels. Some drugs inhibit an enzyme system, making it less effective. DRUG BIOTRANSFORMATION  Also termed as METABOLISM. DRUGS THAT INDUCE DRUGS THAT INHIBIT OR  Is the process whereby the body OR INCREASE DECREASE ACTIVITY inactivates drugs. The enzymes of the ACTIVITY liver are the primary sites for the Nicotine (cigarette Ketoconazole (Nizoral) metabolism of drugs. smoking)  Other tissues and organs (WBC, Gl Tract, Alcohol Amiodarome (generic) Lungs) metabolizes certain drugs to a minor extent. Glucocorticoids Quinidine (generic) (cortisone, others)  Genetic, Environmental and Physiologic factors are involved in the regulation of drug metabolism reactions. EXCRETION  Is the ELIMINATION of a drug FIRST-PASS EFFECT — is a metabolites and, in some cases, of the pharmacological phenomenon in which a active drug itself from the body. medication undergoes metabolism at a specific location in the body. — decreases the active drug's concentration PRIMARY ROUTES OF EXCRETION upon reaching systemic circulation or its site of action. THUS: The injected drug is often more 1. GLOMERULAR FILTRATION — Drugs effective at a lower dose than the oral that have been made water-soluble in the equivalent. Thus, the recommended dose for liver are often readily excreted from the oral drugs can be considerably higher than kidney. the recommended dose for parenteral drugs. — drugs are secreted or reabsorbed through the renal tubule by active transport systems. The active transport ROLE OF DRUG BIOTRANSFORMATION systems that move the drug into the tubule often do so by exchanging it for  The fundamental role of drug- acid or bicarbonate molecules. metabolizing enzymes is to inactivate and detoxify drugs and other foreign 2. GASTROINTESTINAL TRACT compounds ( xenobiotics) that can harm EXCRETION (feces) — via the biliary the body. system will either pass out of the body as feces or be reabsorbed through the enterohepatic circulation after microbial HEPATIC ENZYME SYSTEM deconjugation reactions in the gut. The intracellular structures of the hepatic 3. OTHER ROUTES: evaporation thru the  cells are lined with enzymes packed skin, exhalation from the lungs and together in what is called the hepatic secretions into saliva and breastmilk. microsomal system. Phase I biotransformation involves oxidation, reduction, or hydrolysis of the drug via the cytochrome P450 system of enzymes. Phase Il biotransformation usually involves a conjugation reaction that makes the drug more polar and more readily excreted by the kidneys. — CHANG State needs to enhance further the efficacy of the law against dangerous drugs, it being one of today's more serious social ills. GENERIC DRUGS — A prescription drug that has the same active-ingredient formula as a brand-name drug. Generic drugs usually cost less than brand-name drugs. — Drugs that have been discovered but are not financially viable and therefore have not been "adopted" by any drug company. Orphan drugs may be useful in treating a rare HALF- LIFE — Defined as the amount of time disease, or they may have potentially required for 50% of the drug to be eliminated dangerous adverse effects. Orphan drugs are from the body. often abandoned after preclinical trials Example: A patient is given a 100mg of a — Developed to treat certain rare medical drug that has a half life of 12 hrs, the following conditions. An orphan drug would nit be would be observed; profitable to produce without government assistance, due to the small population of patient affected by the conditions. FACTORS AFFECTING DRUG RESPONSE  Age and Gender  Body weight  Metabolic rate  Illness  Psychological aspects  Tolerance of the medication  Dependence developed from the medication OVER-THE-COUNTER DRUGS — are products that are available without  Cumulative effect of the medication prescription for self-treatment of a variety of complaints. Some of these agents were approved as prescription drugs but later were DRUG LEGISLATION CONTROLLED found to be very safe and useful for patients SUBSTANCES without the need of a prescription. OTC DRUGS EXAMPLES RA 9165 COMPREHENSIVE DANGEROUS  Painkillers DRUGS ACT (PH)  Acne treatment This Act shall be known and cited as the  Heartburn Treatments "Comprehensive Dangerous Drugs Act of 2002".  Fever Reducers It is the policy of the State to safeguard the  Laxatives integrity of its territory and the well-being of its citizenry particularly the youth, from the  Skin Protectants harmful effects of dangerous drugs on their  Sleep Aids physical and mental well-being, and to defend the same against acts or omissions  Stimulants detrimental to their development and preservation. In view of the foregoing, the  Poison Treatments — CHANG PHARMACOLOGY AND THE NURSING  Tertiary Sources: provide an accurate PROCESS depiction of the characteristics of a disease, the nursing interventions and diagnostic tests used, the pharmacologic THE NURSING PROCESS treatment prescribed, dietary interventions and physical therapy  Is crucial for safe medication undertaken, and other factors pertinent to administration. the patient's care requirements.  Nursing Process draws together all of the aspects of the patient:  NURSING DIAGNOSIS Physical  Decision about the need/problem (actual Cultural or at risk for) Cognitive Spiritual  Three parts Sexual Human response to illness Financial "related to"  Recognizing these aspects allows for a as evidenced by" more holistic approach to patient care  Critical Thinking  A research-based organizational framework for professional nursing  Creativity practice  Accurate data collection  Central to all nursing care  It is a statement about the patient's  Encompasses all steps taken by the status and will guide nursing nurse in caring for a patient interventions  Ongoing and constantly evolving process Critical thinking  PLANNING Flexibility is important  Identification of goals — Must be patient- centered  Outcome criteria — Must be SMART, THE NURSING PROCESS Have a time frame  Assessment  Prioritization — Prioritize the problems identified from the assessment data, with  Nursing diagnosis the most severe or life-threatening  Planning (Goals, Outcome criteria) addressed first. Other problems are arranged in descending order of  Implementation importance  Evaluation  IMPLEMENTATION  ASSESSMENT  Initiation and completion of the nursing care plan as defined by the nursing  Collect all relevant data associated with diagnoses and outcome criteria the individual patient's symptoms; his or her history and physical, laboratory, and  Specific interventions related to the diagnostic data patient's pharmacologic needs.  Data sources can be primary, secondary,  Dependent nursing action — Directly or tertiary related to the orders that are written by the doctors who admit the patient.  Sources of Data  Interdependent nursing actions —  Primary Source: reliable information Nurse approach any problems related to coming from the patient. the medication prescribed collaboratively a. Subjective — serve as the baseline with appropriate members of the for the formulation healthcare team. b. Objective — drug-related nursing  Independent nursing action — Nurse diagnosis. verifies the drug order and assumes responsibility for the correct transcription  Secondary Sources: e.g. relatives, of the drug order to the Kardex, significant others, medical records, medication administration record, or laboratory reports, nursing notes, other electronic medical record, medication healthcare professionals. card if applicable. — CHANG  EVALUATION EVALUATION  Ongoing part of the nursing process  Monitoring the patient's response to drug therapy  Determining the status of the goals and outcomes of care 1. Expected outcome 2. Unexpected outcome 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 1. Deficient knowledge (actual, risk) related to the medication regimen (patient education) 2. Noncompliance (actual, risk) related to the patient's value system, cognitive ability, cultural factors, or economic resources. 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 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. 10 rights of medication administration — CHANG

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