Pharmacokinetics and Pharmacodynamics PDF

PHARMACOKINETICS AND PHARMACODYNAMICS NATASHA KAY V. CHAN, RN, MN Pharmacodynamics how the drug affects the body Pharmacokinetics how the body acts on the drug PHARMACODYNAMICS is the study of the interactions between the chemical components of living systems and...

PHARMACOKINETICS AND PHARMACODYNAMICS NATASHA KAY V. CHAN, RN, MN Pharmacodynamics how the drug affects the body Pharmacokinetics how the body acts on the drug PHARMACODYNAMICS is the study of the interactions between the chemical components of living systems and the foreign chemicals, including drugs that enter those systems. Drugs usually work in one of four ways: To replace or act as substitutes for missing chemicals To increase or stimulate certain cellular activities To depress or slow cellular activities To interfere with functioning of foreign cells, such as invading microorganisms or neoplasms leading to cell death (drugs that act in this way are called chemotherapeutic agents) Drugs act in different ways to achieve results: Receptor Sites Specific areas on cell membranes They react with certain chemicals to cause an effect within the cell Enzymes break down the reacting chemicals and open the receptor site for further stimulation Drugs act in different ways to achieve results: a. Agonists Interact directly with receptor sites to cause the same activity that natural chemicals would cause at that site b. Inhibitors Prevent breakdown of natural chemicals that are stimulating the receptor site c. Competitive antagonist React with receptor sites to block normal stimulation, producing no effect d. Non competitive antagonist React with specific receptor sites on a cell and by reacting there prevent the reaction of another chemical with a different receptor site on that cell A. Agonist interaction with receptor site on cell. Molecules of drug A react with specific receptor sites on cells of effector organs and change the cells’ activity. B. Competitive antagonism. Drug A and drug C have an affinity for the same receptor sites and compete for these sites; drug C has a greater affinity, occupies more of the sites, and antagonizes drug A. C. Noncompetitive antagonism. Drug D reacts with a receptor site that is different from the receptor site for drug A but still somehow prevents drug A from binding with its receptor sites.  Drug Enzyme Interaction Drugs also can cause their effects by interfering with the enzyme systems that act as catalysts for various chemical reactions. Enzyme systems work in a cascade fashion, with one enzyme activating another, and then that enzyme activating another, until a cellular reaction eventually occurs.  Selective Toxicity The ability of a drug to attack only those systems found in foreign cells  PHARMACOKINETI CS involves the study of absorption, distribution, metabolism (biotransformation), and excretion of drugs In clinical practice, pharmacokinetic considerations include the onset of drug action (how long it will take to see the beginning of the therapeutic effect), drug half life, timing of the peak effect (how long it will take to see the maximum effect of the drug), duration of drug effects (how long the patient will experience the drug effects), metabolism or biotransformation of the drug, and the site of excretion.  PHARMACOKINETICS Critical Concentration The amount of drug that is needed to cause a therapeutic effect Loading Dose A higher dose than that usually used for treatment to reach critical concentration quickly Dynamic Equilibrium Processes: Absorption from the site of entry Distribution to the active site Biotransformation (metabolism) in the liver Excretion from the body  ABSORPTION Refers to what happens to a drug from the time it is introduced to the body until it reaches the circulating fluids and tissues Drug absorption is influenced by the route of administration  ABSORPTION Process of Absorption Passive diffusion Major process through which drugs are absorbed into the body Occurs across a concentration gradient Movement from an area of greater concentration to lower concentration Active Transport Process that uses energy to actively move a molecule across a cell membrane Filtration Involves movement through pores in the cell membrane either down a concentration gradient or as a result of the pull of plasmaproteins FACTORS THAT AFFECT DRUG ABSORPTION FACTORS THAT AFFECT DRUG ABSORPTION  DISTRIBUTION Involves the movement of a drug to the body’s tissues Factors that affect drug distribution: Drug’s lipid solubility and ionization Perfusion of the reactive tissue  DISTRIBUTION Protein Binding Most drugs are bound to some extent to proteins in the blood to be carried to the circulation. Some drugs are tightly bound and released very slowly casing long duration of action. Some drugs are loosely bound they tend to act quickly and to be excreted quickly. Some drugs compete with each other for protein binding sites, altering effectiveness or causing toxicity when two drugs are given together.  DISTRIBUTION Blood Brain Barrier Is a protective system of cellular activity that keeps many things away from the CNS. Drugs that are highly lipid soluble are more likely to pass through the blood brain barrier and reach the CNS. Drugs that are not lipid soluble are not able to pass the blood brain barrier.  DISTRIBUTION Placenta and Breast Milk Many drugs pass through the placenta and affect the developing fetus in pregnant women. METABOLISM (BIOTRANSFORMATION) The process by which drugs are changed into new, less active chemicals.  First Pass effect Drugs that are taken orally are usually absorbed from the small intestine directly into the portal venous system. The portal veins deliver these absorbed molecules into the liver, which immediately transforms most of the chemicals delivered to it by a series of liver enzymes. These enzymes break the drug into metabolites, some of which are deactivated and can be readily excreted from the body.  EXCRETION Is the removal of a drug from the body. Routes Skin, saliva, lungs, bile and feces Excreted by the kidneys through glomerular filtration  Half life is the time it takes for the amount of drug in the body to decrease to one half of the peak level it previously achieved. For instance , if a patient takes 20 mg of a drug with a half life of 2 hours, 10 mg of the drug will remain 2 hours after administration. Two hours later, 5 mg will be left (one half of the previous level); in 2 more hours, only 2.5 mg will remain. This information is important in determining the appropriate timing for a drug dose or determining the duration of a drug’s effect on the body  FACTORS INFLUENCING DRUG EFFECTS Weight Age People who are much heavier may Children may metabolize drugs differently than adults do and they have immature systems for handling drugs. Older adults require larger dose to get may undergo physical changes that are part of the aging therapeutic effects and people who process. Their bodies may respond very differently in all aspects of pharmacokinetics less effective absorption, less weigh less than the norm may efficient distribution because of fewer plasma proteins and require smaller doses of drugs. less efficient perfusion, altered metabolism of drugs because of age related liver changes, and less effective excretion owning to less efficient kidneys.  FACTORS INFLUENCING DRUG EFFECTS Gender Physiologic Factors Physiological differences between men and women Diurnal rhythm of the nervous and can influence a drug’s effect. When giving IM injections, for example, it is important to remember endocrine systems, acid base balance, that men have more vascular muscles, so the effects hydration, and electrolyte balance can of the drugs will be seen sooner in men than in women. affect the way that a drug works on the Women on the other hand have more fat cells than body and the way that the body handles men do, so drugs that deposit in fat may be slowly the drug. released and cause effects for a prolonged period.  FACTORS INFLUENCING DRUG EFFECTS Pathological Factors Genetic Factors Other pathologic conditions can change Some people lack certain enzyme systems necessary the basic pharmacokinetics of a for metabolizing a drug, whereas others have overactive enzyme systems that cause drugs to be drug. broken down more quickly. Pharmacogenomics is a new area of study that explores the unique differences in response to drugs that each individual possesses based on genetic makeup.  FACTORS INFLUENCING DRUG EFFECTS Immunological Factors Psychological Factors People can develop an allergy to a drug. After The patient’s attitude about a drug has been exposure to its proteins, a person can develop shown to have an effect on how that drug works. antibodies to a drug. With future exposure to the A drug is more likely to be effective if the patient same drug, that person may experience a full blown thinks it will work than if the patient believes it allergic reaction. Sensitivity to a drug can range from will not work. This is called the placebo effect. The mild (e.g., dermatological reactions such as a rash) to patient’s personality also influences compliance more severe (e.g., anaphylaxis, shock, and death with the drug regimen.  FACTORS INFLUENCING DRUG EFFECTS Environmental Factors Some drug effects are enhanced by a quiet, cool, non stimulating environment. For example, sedating drugs are given to help a patient relax or to decrease tension. Reducing external stimuli to decrease tension and stimulation help the drug be more effective. Other drug effects may be influenced by temperature. For example, antihypertensives that work well during cold, winter months may become too effective in warmer environments, when natural vasodilation may lead to a release of heat that tends to lower the blood pressure.  FACTORS INFLUENCING DRUG EFFECTS Tolerance Cumulation Tolerance may arise because of increased If a drug is taken in successive doses at biotransformation of the drug, increased resistance intervals that are shorter than to its effects, or other pharmacokinetic factors. recommended, or if the body is unable to When tolerance occurs, the drug no long causes the same reaction. Therefore, increasingly larger eliminate a drug properly, the drug can doses are needed to achieve a therapeutic effect. accumulate in the body, leading to toxic levels and adverse effects.  FACTORS INFLUENCING DRUG EFFECTS Interactions When two or more drugs or substances are taken together, there is a possibility that an interaction can occur, causing unanticipated effects in the body. Types of Interactions: Drug to Drug or Drug to Alternative Therapy Interactions At the site of absorption During distribution During metabolism During excretion At the sire of action Drug to Laboratory Test Interaction administration of a particular drug may alter results of tests that are done on various chemical levels or reactions as part of a diagnostic study. Drug to Food Interaction Some foods increase acid production, speeding the breakdown of the drug molecule and preventing absorption and distribution of the drug. Some foods chemically react with certain drugs and prevent their absorption into the body.  TOXIC EFFECTS OF DRUGS All drugs are potentially dangerous. Even though chemicals are carefully screened and tested in animals and in people before they are approved for sale, drug products often cause unexpected or unacceptable reactions when they are administered. Drugs are chemicals, and the human body operates by a vast series of chemical reactions.  ADVERSE EFFECTS Are undesired effects that may be unpleasant or even dangerous. They can occur for many reasons, including the following: The drug may have other effects on the body besides the therapeutic effect The patient may be sensitive to the drug being given. The drug’s action on the body may cause other responses that are undesirable or unpleasant. The patient may be taking too much or too little of the drug, leading to adverse effects.  Literary Review 01 Primary Action Development of adverse reaction from simple overdose which can be caused 02 Secondary Action Effects of the drug in addition to the by individual response to the drug, high desired pharmacological effect. or low body weight, age or underlying pathology that alters the effects of the drug This type of adverse effect can be 03 Hypersensitivity avoided by monitoring the patient Excessively responsive to either the carefully and adjusting the prescribed primary or the secondary effects of a dose to fit that particular patient’s drug. It may result from pathological needs. or underlying condition.  DRUG ALLERGY Occurs when the body forms antibodies to a particular drug, causing an immune response when the person is reexposed to the drug. A patient cannot be allergic to a drug that has never been taken, although patients can have cross allergies to drugs within the same drug class as one formerly taken. Four main classifications: Anaphylactic reactions Cytotoxic reactions Serum sickness Delayed reactions  ANAPHYLACTIC Reaction ALLERGY TYPE ASSESSMENT INTERVENTIONS This allergy involves an Hives, rash, Administer epinephrine. antibody that reacts with Massage the site to speed specific sites in the body difficulty absorption rate. Repeat the to cause the release of breathing, dose every 15 20 min, as appropriate. Notify the chemicals, including increased BP, prescriber and/ or primary histamine, that produce immediate reactions dilated pupils, caregiver and discontinue the drug. Be aware that (mucous membrane diaphoresis, prevention is the best swelling and constricting “panic” feeling, treatment. Counsel patients bronchi) that can lead with known allergies to wear to respiratory distress and increased heart identification and, if even respiratory arrest. rate, respiratory appropriate, to carry an emergency epinephrine kit. arrest  CYTOTOXIC Reaction ALLERGY TYPE ASSESSMENT INTERVENTIONS This allergy involves Complete blood count Notify the prescriber antibodies that showing damage to and/or primary circulate in the blood blood forming cells caregiver and (decreased hematocrit, discontinue the drug. and attack antigens white blood cell count, Support the patient to (the drug) on cell and platelets); liver prevent infection and sites, causing death of function tests show conserve energy until that cell. This reaction elevated liver enzymes; the allergic response is is not immediate but renal function test shows over. may be seen over a decreased renal few days function  SERUM SICKNESS REACTION ALLERGY TYPE ASSESSMENT INTERVENTIONS This allergy involves Itchy rash, high Notify the prescriber antibodies that and/or primary fever, swollen circulate in the blood caregiver and lymph nodes, discontinue the drug. and cause damage swollen and painful Provide comfort to various tissues by joints, edema of measures to help the depositing in blood patient cope with the vessels. This reaction the face and limbs signs and symptoms may occur up to 1 wk (cool environment, skin or more after care, positioning, ice to exposure to the drug. joints, administer antipyretics or anti inflammatory agents, as  DELAYED ALLERGIC REACTION ALLERGY TYPE ASSESSMENT INTERVENTIONS This reaction Rash, hives, Notify the occurs several prescriber and/or swollen joints primary caregiver hours after (similar to the and discontinue exposure and drug. Provide skin involves reaction to care and comfort antibodies that poison ivy) measures that may are bound to include antihistamines or specific white topical blood cells. corticosteroids.  DRUG INDUCED TISSUE AND ORGAN DAMAGE >Dermatologic Reactions >Adverse reactions involving the skin. –Rashes Assessment: Hives, rashes, and other dermatological lesions. Severe reactions include exfoliative dermatitis, characterized by rash and scaling, fever, enlarged lymph nodes, enlarged liver, and potentially fatal erythema multiforme exudativum (Steven Johnson’s syndrome). Interventions: Provide frequent skin care; instruct the patient to avoid rubbing, wearing tight or rough clothing, and using harsh soaps or perfumed lotions; and administer antihistamines, as appropriate. In severe cases, discontinue the drug and notify the prescriber. Topical corticosteroids, antihistamines and emollients  EXFOLIATIVE DERMATITIS STEVEN JOHNSON’S SYNDROME  DRUG INDUCED TISSUE AND ORGAN DAMAGE >Dermatologic Reactions >Adverse reactions involving the skin. –Stomatitis Inflammation of the mucous membranes, can occur because of a direct toxic reaction to the drug or because the drug deposits in the end capillaries in the mucous membranes, leading to inflammation. Assessment Swollen gums, inflamed gums (gingivitis), and swollen and red tongue (glossitis). Difficulty of swallowing, bad breath, and pain in the mouth and throat. Interventions Provide frequent mouth care with a non irritating solution. Small frequent meals, dental consultation. Use of anti fungal agents and/or local anesthetics are sometimes used. STOMATITIS  DRUG INDUCED TISSUE AND ORGAN DAMAGE >Superinfections >Infections caused by organisms that are usually controlled by the normal flora Assessment: Fever, diarrhea, black or hairy tongue, inflamed and swollen tongue (glossitis), mucous membrane lesions, and vaginal discharge with or without itching. Interventions: Provide supportive measures (frequent mouth care, skin care, access to bathroom facilities, small and frequent meals). Administer antifungal therapy.  DRUG INDUCED TISSUE AND ORGAN DAMAGE >Blood Dyscrasia >Bone marrow suppression caused by drug effects. This occurs when drugs that can cause cell death ( antineoplastics , antibiotics) are used. Assessment: Fever, chills, sore throat, weakness, back pain, dark urine, decreased hematocrit, low platelet count (thrombocytopenia), low white blood cell count (leukopenia), and reduction of all cellular elements of the complete blood count Interventions: Monitor blood counts. Provide supportive measures (rest, protection from exposure to infections, protection from injury, avoidance of activities that might result in injury or bleeding). Discontinue the drug until bone marrow recovers.  DRUG INDUCED TISSUE AND ORGAN DAMAGE Toxicity –Potentially serious reactions to a drug –Liver injury Assessment: Fever, malaise, nausea, vomiting, jaundice, change in color of urine and stools, abdominal pain or colic, elevated liver enzymes, alterations in bilirubin levels, and changes in clotting factors. Interventions Discontinue the drug and notify the prescriber. Offer supportive measures such as small frequent meals, skin care, a coold environment, and rest periods.  DRUG INDUCED TISSUE AND ORGAN DAMAGE Toxicity -Potentially serious reactions to a drug –Renal Injury Assessment: Elevated BUN, elevated creatinine concentration, decreased hematocrit, electrolyte imbalances, fatigue, malaise, edema, irritability, and skin rash. Interventions: Notify prescriber and discontinue drug. Offer supportive measures (positioning, diet and fluid restrictions, skin care, electrolyte therapy, res periods, a controlled environment). Dialysis for severe cases. –Poisoning Occurs when an overdoese a drug damages multiple body systems, leading to the potential for fatal reactions.  DRUG INDUCED TISSUE AND ORGAN DAMAGE ›Alterations in Glucose Metabolism –Hypoglycemia >Low serum glucose concentration Assessment: Fatigue, drowsiness, hunger, anxiety, headache, cold clammy skin, shaking and lack of coordination (tremulousness), increased heart rate, increased blood pressure, numbness and tingling of the mouth, tongue, and/or lips, confusion, and rapid and shallow respirations. In severe cases seizures and/or coma Interventions: Restore glucose orally or intravenously, Provide supportive measures (skin care, environmental control of light and temperature, rest). Safety measures to prevent falls, Monitor glucose levels to help stabilize the situation.  DRUG INDUCED TISSUE AND ORGAN DAMAGE ›Alterations in Glucose Metabolism –Hyperglycemia >High serum glucose levels Assessment: Fatigue, increased urination (polyuria), increased thirst (polydipsia), deep respirations kussmaul respirations), restlessness, increased hunger (polyphagia), nausea, hot or flushed skin, and fruity odor to breath. Interventions: Insulin therapy. Provide support to help the patient deal with the signs and symptoms.  DRUG INDUCED TISSUE AND >Electrolyte Imbalances ORGAN DAMAGE –Hypokalemia >Low serum potassium levels Assessment: Weakness, numbness and tingling in the extremities, muscle cramps, nausea, vomiting, diarrhea, decreased bowel sunds , irregular pulse, weak pulse, orthostatic hypotension, and disorientation. In severe cases, paralytic ileus (absent bowel sounds) may occur. Interventions: Replace serum potassium and carefully monitor serum levels. Supportive therapy of signs and symptoms and cardiac monitoring.  DRUG INDUCED TISSUE AND ORGAN DAMAGE >Sensory Effects a. Ocular Damage –Damage to the tiny blood vessels of the retina Assessment Blurring of vision, color vision changes, corneal damage, and blindness. Interventions Monitor vision. Consult with prescriber and discontinue drug as appropriate. Monitor lighting and exposure to sunlight.  DRUG INDUCED TISSUE AND ORGAN DAMAGE >Neurologic Effects –General Central Nervous System Effects Assessment: Confusion, delirium, insomnia, drowsiness, hyperreflexia or hyporeflexia , bizarre dreams, hallucinations, numbness, tingling and paresthesias Interventions: Provide safety measures. Avoid dangerous situations such as driving or operating dangerous machinery.  DRUG INDUCED TISSUE AND ORGAN DAMAGE ›Neurologic Effects –Atropine like (anticholinergic) Effects Assessment: Dry mouth, altered taste perception, dysphagia, heartburn, constipation, bloating,paralytic ileus, urinary hesitancy and retention, impotence, blurred vision, cyclopegia , photophobia, headache, metal confusion, nasal congestion, palpitations, decreased sweating, and dry skin. Interventions: Provide sugarless lozenges and mouth care. Arrange for bowel program as appropriate, voiding before taking drugs, provide safety, medication for headache and nasal congestion.  DRUG INDUCED TISSUE AND ORGAN DAMAGE Neurologic Effects >Parkinson like Syndrome -Affects dopamine levels in the brain Assessment: Lack of activity, akinesia, muscular tremors, drooling, changes in gait, rigidity, extreme restlessness or jitters (akathisia), or spasms (dyskinesia). Interventions: Discontinue the drug. Anticholinergics and antiparkinsons. Provide small, frequent meals. Provide safety measures  DRUG INDUCED TISSUE AND ORGAN DAMAGE Neurologic Effects –Neuroleptic Malignant Syndrome -A generalized syndrome that includes high fever Assessment: Extrapyramidal symptoms (slowed reflexes, rigidity, involuntary movements, hyperthermia), autonomic disturbances (hypertension, tachycardia, fever) Interventions: Discontinue the drug Give anticholinergics and antiparkinsons Provide measure to lower temperature Provide safety  DRUG INDUCED TISSUE AND ORGAN DAMAGE Teratogenicity Drugs that affect the developing fetus or embryo which may cause death or congenital defects  NURSING PROCESS IN DRUG THERAPY Nursing is a complex art and science that provides for nurturing and care of the sick, as well as prevention and education services. Components of the nursing assessment (history of past illnesses and the current complaint, as well as a physical examination) provide a database of baseline information to ensure safe administration of a drug and to evaluate the drug’s effectiveness and adverse effects. Nursing assessment must include information on the history of past illnesses and the current complaint, as well as a physical examination; this provides a database of baseline information to ensure safe administration of a drug and to evaluate the drug’s effectiveness and adverse effects.  NURSING PROCESS IN DRUG THERAPY Nursing diagnoses are developed from the information gathered during the assessment phase of the nursing process. A nursing diagnosis states the actual or potential response of a patient to a clinical situation. Implementation involves taking the information gathered and synthesized into nursing diagnoses to plan the patient care. This process includes determining the desired patient outcomes, setting goals for safe and effective drug administration, providing comfort measures to help the patient cope with the therapeutic or adverse effects of a drug, and providing patient and family education to ensure safe and effective drug therapy  NURSING PROCESS IN DRUG THERAPY Evaluation is part of the continuing process of patient care that leads to changes in assessment, diagnosis, and intervention. The patient is continually evaluated for therapeutic response, the occurrence of adverse drug effects, and the occurrence of drug drug, drug food, drug alternative therapy, or drug laboratory test interactions. A nursing care guide and patient education materialscan be prepared for each drug being given, using information about a drug’s therapeutic effects, adverse effects, and special considerations.  ASSESSMENT This involves systematic, organized collection of data about the patient. History is an important element of assessment related to drug therapy because his or her past experiences and illnesses can influence a drug’s effect. Knowledge of this important information before beginning drug therapy will help to promote safe and effective use of the drug and prevent adverse effects, clinically important drug drug, drug food, or drug alternative therapy interactions, and medication errors.  ASSESSMENT HISTORY Chronic Condition Drug Use Allergies Level of Education and Understanding Social Supports Financial Supports Pattern of Healthcare  ASSESSMENT Physical examination >Weight Helps to determine whether the recommended drug dose is appropriate >Age Patients at the extremes of the age spectrum children and older adults often require dose adjustments based on the functional level of the liver and kidneys and the responsiveness of other organs. >Physical Parameters related to Disease or Drug Effects The specific parameters that need to be assessed depend on the disease process being treated and on the expected therapeutic and adverse effects of the drug therapy.  NURSING DIAGNOSIS Is simply a statement of the patient’s status from a nursing perspective. The nurse analyzes the information gathered during assessment to arrive at some conclusions that lead to a particular goal and set of interventions. A nursing diagnosis shows actual or potential alterations in patient function based on assessment of the clinical situation. Because drug therapy is only a small part of the overall patient situation, nursing diagnoses that are related to drug therapy must be incorporated into a total picture of the patient.  PLANNING Involves taking and prioritizing the information gathered and synthesized in the nursing diagnoses to plan the patient care. This process includes setting goals and desired patient outcomes to assure safe and effective drug therapy. These outcomes usually involve ensuring effective response to drug therapy, minimizing adverse effects, and understanding the drug regimen.  IMPLEMENTATION Involves nursing interventions aimed at achieving the goals of outcomes determined in the planning phase. Three types of nursing interventions are frequently involved in drug therapy: drug administration provision of comfort measures patient/family education.  Proper Drug Administration 10 Rights to ensure safe and effective drug administration: Right patient Right drug Right route Right dose Right time Right assessment Right documentation Right evaluation Right education Right to refuse  IMPLEMENTATION Comfort Measures Placebo effect The anticipation that a drug will be helpful (placebo effect) has proven to have tremendous impact on the actual success of drug therapy. Therefore, the nurse’s attitude and support can be a critical part of drug therapy. For example , a back rub, a kind word, and a positive approach may be as beneficial as the drug itself Managing Adverse effects Interventions can be directed at promoting patient safety and decreasing the impact of the anticipated adverse effects of a drug. Such interventions include environmental control (e.g., temperature, light), safety measures (e.g., avoiding driving, avoiding the sun, using side rails), and physical comfort measures (e.g., skin care, laxatives, frequent meals).  IMPLEMENTATION Comfort Measures Lifestyle Adjustment Some medications and their effects require that a patient make changes in his or her lifestyle. Patient and Family Education With patients becoming increasingly responsible for their own care, it is essential that they have all of the information necessary to ensure safe and effective drug therapy at home.  IMPLEMENTATION INCLUDE THE FOLLOWING KEY ELEMENTS IN ANY DRUG EDUCATION PROGRAM Name , dose, and action of drug Timing of administration Special storage and preparation instructions Specific OTC drugs or alternative therapies to avoid Special comfort measures Safety measures Specific points about drug toxicity Specific warnings about drug discontinuation  EVALUATION Is part of the continuing process of Some drug therapy require patient care that leads to changes in evaluation of specific assessment, diagnosis, planning, and intervention. therapeutic drug levels The patient is continually evaluated for therapeutic response, the occurrence of adverse drug effects, and the occurrence of drug drug, drug food, drug alternative therapy, or drug laboratory test interactions. MEDICATION ERRORS It reported that 44,000 reported deaths in hospitals each year occurred from medication errors and that the number could probably be closer to 98,000.  Patient’s Role Keep a written list of medication you are taking. Know what each of your drugs is being used to treat. Read the labels, and follow the directions Store drugs in a dry place, away from children and pets. Never use adult medications to treat a child Read all labels before giving your child a drug Measure liquid medication using appropriate measuring devices Call your health care provider immediately if your child seems to get worse Do not hesitate to ask questions  INSTRUCTIONS TO PARENTS Keep a list of all medications you are giving your child, including prescription, OTC, and herbal medications. Never use adult medications to treat a child. Read all labels before giving your child a drug. Measure liquid medications using appropriate measuring devices. Call your healthcare provider immediately if your child seems to get worse or seems to be having trouble with a drug When in doubt, do not hesitate to ask questions.