Pharm Unit 1 Study Guide
19. Explain how enterohepatic recirculation affects drug activity
enterohepatic recirculation: how bile (stored in the gallbladder) is circulated back to the liver, drugs may be recirculated numerous times with the bile=(half-life)extended stay in the body and prolonged activity (i.e. antibiotics). Could continue for several weeks after therapy has ended. Liver eventually metabolizes and kidneys excrete.
Excretion
the elimination of meds from the body, primarily through the kidneys. Liver, lungs, bowel, & exocrine glands help out too. Renal dysfunction may lead to an increase in duration and intensity of med response, so BUN and creatinine levels should be monitored. (class) - how fast the drug clears your system, referred to as Cl. Also controlled by enzymes, cytochrome 450. Cp450 inducers, Cp450 inhibitors.
Distribution
the transportation of medications to sites of action by bodily fluids. It depends on protein binding sites (for transport) and their volume of distribution. We call this Vd.
17. Explain how a biosimilar drug differs from its reference product.
• Biosimilar drugs - Comparable effectiveness and safety to FDA approved biologic products - Not exact, duplicate copy of original medication (reference product) - Should not be called a generic medication
10. Evaluate the role of the U.S. Food and Drug Administration in the drug approval process.
• Oldest drug regulatory agency in the world • Organized into seven branches • Center for Drug Evaluation and Research (CDER) regulates drug safety. drugs must pass to be marketed. • Center for Biologics Evaluation and Research (CBER) regulates biological safety, drugs from living sources. • Center for Food Safety and Applied Nutrition (CFSAN) oversees herbals, dietary supplements, cosmetics.
40. Discuss the nursing and pharmacologic implications associated among the pediatric developmental age groups.
• Pharmacotherapy of the infant - Infancy period ▪Birth to 12 months of age - Neonatal period ▪First 28 days of life - Nursing care and pharmacotherapy ▪Directed toward the safety of the infant ▪Proper dosing - Nursing interventions and parental teaching points ▪Hold and cuddle infant while administering medications. -Offer pacifier if infant on fluid restrictions. ▪Medications -Administer via droppers into ears, eyes, nose, or mouth • Pharmacotherapy of the toddler - Toddlerhood is from 1 to 3 years of age ▪At 1 year, most pharmacokinetic responses similar to an adult's - Two-year-olds metabolize drugs at a very rapid rate - Drug doses must be adjusted to maintain therapeutic levels. - They can swallow liquids and chew solid medications. ▪Medication may be a flavored elixir. - Poisoning is common at this age. - Nursing interventions and parental teaching points ▪Short, concrete explanations ▪Physical comfort or verbal praise following drug administration is important. ▪Mix unpleasant-tasting medications with jam, syrup, or fruit puree. ▪Medications followed by carbonated beverage or mint-flavored candy • Pharmacotherapy of preschoolers - Preschool child ranges from 3 to 5 years of age. - In general, principles of medication administration that pertain to toddler apply. - Children over age of 4 may require two adults to administer medications. - Child may benefit from play-acting troubling experiences with dolls before and after procedure. • Pharmacotherapy of school-age child - School-age child is 6 to 12 years of age - Rapid mental, physical, and social development occurs - Early ethical‒moral development begins - Most children remain healthy - School-age children usually more cooperative. ▪Understand relationship between medication, feeling better - More detailed explanations may be of value - School-age children may take chewable tablets, swallow tablets or capsules. - Resist injections - Ventrogluteal site preferred for IM injections • Pharmacotherapy of the adolescent - Adolescent is ages 13 to 16 years. - Rapid physical growth and psychological maturation have great impact on personality development. - Strongly relates to peers, wants and needs their support, presence, and approval - Keep medications out of sight. - Parents should be taught signs and symptoms of drugs abused by teens. ▪Marijuana ▪Inhalants ▪Methamphetamine - Common needs for pharmacotherapy ▪Skin problems ▪Headaches ▪Menstrual symptoms ▪Sex-related concerns ▪Eating disorders ▪Alcohol and tobacco use ▪Sports-related injuries
4. Identify and explain the major (safety, efficacy, selectivity) & minor (reversibility, predictability, convenience, free from other drugs or food, cost effective, chemical stability, simple name) properties/characteristics of an ideal drug
(safety, efficacy, selectivity) are the most important because patient safety is important, efficacy is how well the drug treats, prevents or cures the patient, selectivity is that the drug only effects the target area and nothing else. (reversibility, predictability, convenience, free from other drugs or food, cost effective, chemical stability, simple name) are all good features in a drug, but can be enhanced or inhibited by other drugs or situations.
37. Identify factors that influence the transfer of drugs into breast milk.
- Plasma drug level in the mother - Solubility of the drug - Molecular size - Protein binding - Drug ionization - Drug half-life
26. Distinguish between an agonist, partial agonist, and antagonist
-Blocking anything from fitting in the receptor perfectly (antagonists) noncompetitive: no fight for the binding (i.e. Morphine: antagonist is called Narcan—no matter how much morphine is in the bloodstream it will not work because the Narcan is noncompetitive) competitive : competition—amount of drug you give, the one with the higher concentration will reach the most number of receptors and will win -Fit perfectly and work to enhance (agonists) -Somewhat fit, weaker effect than agonist (partial agonist) Intrinsic activity- drugs that have the ability to bind to a receptor and produce a strong action is said to have a high intrinsic activity.
2. Define, compare and contrast the terms drug, pharmacology, and pharmacotherapy.
-drug= any substance that is taken to prevent, cure, or reduce symptoms of a medical condition -pharmacology= the study of meds -pharacotherapy= the application of drugs for the purpose of disease prevention and treatment of suffering
Metabolism
AKA Biotransformation. changes meds into less active or inactive forms by the action of enzymes. Occurs primarily in the liver; also happens in kidneys, lungs, bowel & blood. Affects the drug's half-life.
24. Compare and contrast the terms "potency" and "efficacy"
-potency: strength of a drug at a specified concentration or dose Potency= how much that concentration is effecting someone at that dose i.e. it takes drug b 10x the amount than drug a to effect someone the same **could take 1mg of a drug and 200mg of another, but the therapeutic response would only matter (does not mean that it is more potent) -efficacy: the greatest maximal response that can be produced from a particular drug Efficacy is all that really matters. Drug A is much more effective than drug B is. Will effect how they are prescribed. An effective drug is more important than a potent drug
6. Identify what a prototype drugs and how is it used to study pharmacology.
-protype drug: the agent to which all other drugs in a class are compared -they can predict the actions/adverse effects of other drugs in their class
9. Outline the key U.S. drug regulations and explain how each has contributed to the safety and effectiveness of medications.
1906-The Pure Food and Drug Act prohibits the manufacture and sale of adulterated or misbranded foods, drugs, and medications. 1938-The Food, Drug, and Cosmetic Act is the first law preventing the marketing of drugs not thoroughly tested. 1970-The Comprehensive Drug Abuse Prevention and Control Act (also known as the Controlled Substances Act) organizes regulated drugs (including opiates, cocaine, cannabis, stimulants, depressants, and hallucinogens) into five schedules and imposes restrictions and penalties. 1997-The FDA Modernization Act reauthorizes the Prescription Drug User Fee Act, representing the largest reform effort of the drug review process since 1938. 2007-The FDA Amendments Act (FDAAA) of 2007 reauthorizes and expands the Prescription Drug User Fee Act, the Modernization Act, the Best Pharmaceuticals for Children Act, and the Pediatric Research Equity Act.
39. Explain how differences in pharmacokinetic & pharmacodynamic variables can impact drug response in pediatric patients.
Absorption can be affected by the differences in gastric pH and stomach emptying time that have been observed in the pediatric population. Low plasma protein concentrations and a higher body water composition can change drug distribution. Metabolic processes are often immature at birth, which can lead to a reduced clearance and a prolonged half-life for those drugs for which metabolism is a significant mechanism for elimination. Renal excretion is also reduced in neonates due to immature glomerular filtration, tubular secretion, and reabsorption. Limited data are available on the pharmacodynamic behavior of drugs in the pediatric population. Understanding these age effects provide a mechanistic way to identify initial doses for the pediatric population. The various factors that impact pharmacokinetics and pharmacodynamics mature towards adult values at different rates, thus requiring continual modification of drug dose regimens in neonates, infants, and children. Pharmacodynamics the branch of pharmacology concerned with the effects of drugs and the mechanism of their action.
Absorption
Absorption is the movement of a drug from its site of administration into the blood. Most drugs are absorbed by passive absorption but some drugs need carrier mediated transport. Small molecules diffuse more rapidly than large molecules. Lipid soluble non - ionized drugs are absorbed faster. Absorption is affected by blood flow, pain stress etc.
18. Identify the four primary processes of pharmacokinetics
Absorption, distribution, metabolism, excretion are all forms of movement through the body
28. Describe the mechanisms and be able to give examples of drug interactions as they relate to alter absorption, distribution, metabolism, or excretion
Absorption:slow peristalsis=prolong absorption, taking drugs before/ after food on an empty stomach,teaching not to take drugs with antacids or milk, alteration of pH Distribution: displacement of drug from plasma protein binding site(increases bc of free drugs), plasma pH altered can effect ionization of drugs (i.e. alkaline infused increases pH then acidic drugs blah blah) Metabolism: stimulation of CYP induction decreases drug effect (and opposite), enzyme inhibition, enzyme induction Excretion: increased bowel movements or fluid output increases potential drug effect, decreased bowel movements or fluid intake increases potential drug effect.
Discuss factors affecting drug absorption
Administration route of the drug Food or fluids administered with the drug Dosage formulation (concentration of the drug) Drug ionization Status of the absorptive surface (how large/intact is the surface?) Rate of blood flow to the small intestine (more alkaline and more vili and larger SA than the stomach) (i.e. Crohn's disease) Acidity of the stomach (diabetes, IBS, stays in stomach longer) Status of GI motility
29. Define what an adverse drug reaction (ADR) is, give examples of them and include what distinguishes what a side effect is.
Adverse Drug Reaction is a reaction which is mentioned for specific drug in the prescription explanation given by drug manufacturer, in other words it is an objective adverse reaction evidence-based on the findings from the clinical trials. Severe reaction Side effects are types of drug effects that are predictable and which may occur even in therapeutic doses. Minor reaction
34. Identify and explain how individual variation can change drug response in terms of body weight, composition, age, during pathological process (kidney, liver, acid-base, electrolyte), gender, race, comorbidity, diet, compliance and genetic variants.
All of these different from person to person, drugs do not work the same for everyone. It only takes one of the items listed to change how the medication reacts with the patient.
42. Explain how differences in pharmacokinetic & pharmacodynamic variables can impact drug response in older adult patients.
Ask a patient to disclose all medications - OTC, herbals, or dietary supplements - Can interact with prescription medications pg. 125-126 • Absorption - Slower, yet absorption still complete - Increased risk of GI adverse effects possible • Distribution - Fat-soluble drugs stored in fat tissue - Water-soluble drugs ▪ Higher concentrations due to decreased total-body water - Liver function declines ▪ Higher concentrations of active drug - Decreased drug binding to plasma proteins ▪ Increased free drug concentrations ▪ Greater pharmacologic effect - Increased permeability of blood‒brain barrier ▪ Enhanced CNS effects of certain drugs • Metabolism - Reduced hepatic function - Decreased liver mass - Diminished blood flow - Alteration in activity of hepatic enzymes • Excretion - Kidneys primary site - Slower clearance of drugs from body - Diminished renal function consistent from patient to patient • Pharmacodynamic changes - Decreased numbers of receptors and - Changes in receptor sensitivity ▪ Decreased response to beta-adrenergic agonists and antagonists ▪ Increased response to anticholinergics
32. Explain how a nurse can reduce, minimize or prevent ADRs in patients.
Assessment- information gathering phase as very specific questions Planning- setting priorities, identifying patient-centered goals and expected outcomes, and prescribing nursing interventions Implementation- when engaged in a medication-related task, focus entirely on the task. Positively id the patient, use correct standard procedures, calculate dosage correctly, open medication in front of patient, record the meds admin and dosage info on MAR immediately after admin, and always make sure the patient swallowed an oral med. Evaluation- assess the patient for expected therapeutic outcomes and determine if any adverse effects have occurred. Record results
Discuss how drugs are distributed throughout the body UPDATE get definitions
Blood flow to tissues- drug solubility (lipid/water)- tissue storage- drug-protein binding- special barriers (blood-brain or fecal-placental)- enteric-coated- -Areas of rapid distribution: heart, liver, kidneys, brain -Areas of slow distribution: muscle, skin, fat
30. Define and distinguish between a carcinogen, mutagen, teratogen, iatrogenic agents are.
Carcinogen: chemicals, radiation, viruses that cause or promote cancer Mutagen: chemicals and radiation that cause inheritable changes (mutations) in the DNA molecules in the genes found on chromosomes. Teratogen: can cause birth defects, but safe if taken by someone that doesn't have the potential to become pregnant. Men and postmenopausal women. Iatrogenic agents: conditions do not necessarily result from medical errors, such as mistakes made in surgery, or the prescription or dispensing of the wrong therapy, such as a drug.
38. Differentiate among the U.S. Food and Drug Administration pregnancy risk categories.
Category A: Controlled studies in women fail to demonstrate a risk to the fetus in the first trimester (and there is no evidence of a risk in later trimesters), and the possibility of fetal harm appears remote. Category B: Either animal-reproduction studies have not demonstrated a fetal risk but there are no controlled studies in pregnant women or animal-reproduction studies have shown an adverse effect (other than a decrease in fertility) that was not confirmed in controlled studies in women in the first trimester (and there is no evidence of a risk in later trimesters). Category C: Either studies in animals have revealed adverse effects on the fetus (teratogenic or embryocidal, or other) and there are no controlled studies in women or studies in women and animals are not available. Drugs should be given only if the potential benefit justifies the potential risk to the fetus. Category D: There is positive evidence of human fetal risk, but the benefits from use in pregnant women may be acceptable despite the risk (e.g., if the drug is needed in a life-threatening situation or for a serious disease for which safer drugs cannot be used or are ineffective). Category X: Studies in animals or human beings have demonstrated fetal abnormalities, or there is evidence of fetal risk based on human experience, or both, and the risk of the use of the drug in pregnant women clearly outweighs any possible benefit. The drug is contraindicated in women who are or may become pregnant.
Explain mechanisms by which drugs cross plasma membranes via absorption?
Channels and pores, transport systems/p-glycoproteins, direct penetration of the membrane
8. Identify the classic "five rights (patient, drug, dose, route, time)" and the additional rights (assessment, evaluation, documentation, education, refusal) and give the rationale for safe medicine administration
Classic 5 Rights Patient- • Always check patient's identification bracelet. • Ask patient to state their name and birth date. Drug- • Perform a triple check of the medication's label • When retrieving the medication. • When preparing the medication. • Before administering medication to patient. • Always check the medication label with the physician's orders. Dose- • Check label for medication concentration. • Compare prepared dose with medication order. • Triple all medication calculations. • Check all medication calculations with another nurse. Route- • Verify medication route with medication order before administering. • Medication may only be administered via route specified in order. Time- • Verify schedule of medication with order. 1. Date 2. Time 3. Specified period of time • Check last dose of medication given to patient. • Administer medication within 30 minutes of schedule. Additional Rights Assessment- • Properly assess patient and tests to determine if medication is safe and appropriate. • If deemed unsafe or inappropriate, notify ordering physician and document notification. • Document that medication was not administered and the reason that dose was skipped. Evaluation- After the medication has been administered • Assess patient for any adverse side effects. • Assess patient for effectiveness of medication. • Compare patient's prior status with post medication status. • Document patient's response to medication. Documentation- • Never document before medication is administered Education- • Inform patient of medication being administered. • Inform patient of desired effects of medication. • Inform patient of side effects of medication. • Ask patient if they have any known allergies to medication. Refusal- • The legally responsible party (patient, parent, family member, guardian, etc.) for patient's care has the right to refuse any medication. • Inform responsible party of consequences of refusing medication. • Verify that responsible party understands all of these consequences. • Notify physician that ordered medication and document notification. • Document refusal of medication and that responsible party understands consequences. If all of these Rights are followed properly then the chance of adverse effects.
12. Explain the role of a placebo in new drug testing.
Control group - receive either the standard treatment or a placebo to see how their treatment compares with the proposed treatment. Randomization - places clinical subjects randomly into the control or test groups to increase the reliability and validity of the experiment and to prevent allocation bias. Blinding - people involved are unaware of which group the subjects are in single blinding- the subjects are unaware double blinding- both the subjects and researchers are unaware Double blind studies are more objective.
7. Identify and explain the responsibilities of the nurse in drug administration as part of an interprofessional team (assessment, dosage & administration, promotion of therapeutic effect, minimizing adverse effect, minimizing adverse reactions, deciding PRN, evaluating responses, managing toxicity, educating of medication).
Drug name and classification, intended use, mechanism of action, contraindications, adverse effects, special considerations, route, usual dose, on-set, duration, why drug was prescribed
14. Explain how scheduled drugs are classified and regulated
Drugs with high potential for dependence or frequently abused Sale and distribution are highly restricted *Placed in one of five categories called scheduled 1: cannot be prescribed in the US (heroine) 2,3,4,5: need a controlled substance license to prescribe Registration number needed to purchase and prescribe Special restrictions Drug Schedule Abuse Potential Examples Therapeutic Use I Highest Heroin, GHB, LSD, marijuana, MDMA, mescaline, methaqualone, methcathinone, peyote, and psilocybin No currently acceptable medical use; no prescriptions may be written II High Potent opioids (such as codeine in high doses, fentanyl, methadone, morphine, oxycodone, meperidine), amphetamine, cocaine, methamphetamine, ethylphenidate, PCP, and short-acting barbiturates Have currently accepted medical use but use may be severely restricted; normally no refills are permitted (but there are exceptions) III Moderate Anabolic steroids, buprenorphine ketamine, codeine (lower doses compounded with aspirin or acetaminophen), hydrocodone (lower doses compounded with aspirin or acetaminophen), and intermediateacting barbiturates Have currently accepted medical use; less stringent controls than Schedule II drugs; five refills allowed in a 6-month period IV Low Benzodiazepines (such as alprazolam, diazepam, midazolam, temazepam), long-acting barbiturates, meprobamate, pentazocine, tramadol, and zolpidem. Have currently accepted medical use; similar controls to Schedule III drugs; five refills allowed in a 6-month period V Lowest Cough medicines with codeine, antidiarrheal medicines with small amounts of opioids. Have currently accepted medical use; similar controls to Schedule III and IV drugs
15. Discuss the rationale for a pharmaceutical company receiving exclusivity for the marketing of a new drug.
Each drug receives period of exclusivity. ▪ Competing companies not allowed to market generic versions, because the Trade Name company needs time to recope the money they spent to develop the drug. - Pharmaceutical companies market their trade-name drugs. - Claim significant difference between tradename and generic. - Consumer advocates argue generic should be available. - Cost difference between generic and tradename can be significant.
Explain the importance of the median effective dose to clinical practice
Effective dose (ED50) in 50% of people who take it; nurse should realize that the standard dose predicts a satisfactory therapeutic response in half of those who take it, important to not just know usual doses, but to see how your patient responds to standard doses and make the adjustment for them.
21. Explain the applications of a drug's plasma half life to pharmacotherapy
Half life: the time it takes for one half of the original amount of a drug in the body to be removed, drugs have 4x half-life. ex. a drug with a half-life of 8 mins, the drug is considered to be eliminated at 32mins.
22. Differentiate between loading and maintenance doses
Loading dose= higher amount of drug, often given only once or twice to "prime" the bloodstream with levels sufficient to quickly induce a therapeutic response Maintenance doses: after loading dose before levels drop back toward zero, these doses are given to keep the plasma drug concentration in the therapeutic range.
41. Describe nursing interventions for minimizing adverse effects during pediatric pharmacotherapy.
Majority of adverse effects dose related. - Close attention must be paid to proper dose and frequency of drug administration.
33. Explain the two organ-specific toxicities: Hepatotoxic drugs & Prolonged QT interval drugs and why they deserve special consideration
Many drugs are toxic to specific organs Therefore patients must be monitored when on these drugs for signs for developing injury Patients should also be educated on these signs Two important types of organ-specific toxicity 1. Injury to the liver 2. Altered cardiac function, as evidence by prolonged QT interval on the electrocardiogram Hepatotoxic drugs Drugs that undergo metabolism by the liver, and are converted into toxic products that can injure liver cells Interval drugs or QT drugs The ability of some medication to prolong the QT interval on the electrocardiogram, thereby creating a risk of serious dysrhythmias QT interval is a measure of the time required for the ventricles to depolarize after each contraction When QT is prolonged patients can develop a dysrhythmia known as torsades de pointes, which can progress to potentially fatal ventricular fibrillation (when the heart quivers instead of pumps)
Compare/contrast median lethal dose and median toxicity dose
Median lethal dose(LD50)= determined in animals in preclinical experiments during the drug development. (kills 50% of a group of animals) Median toxicity dose(TD50)= determined in animals or humans in clinical trials (produce a given toxicity in 50% of a group of patients)
31. Describe what a medication error is, who makes them, types of errors, causes of errors, and how to reduce them
Medication errors are preventable events due to the inappropriate use of medications. Medication errors that cause harm are called preventable adverse drug events. If a medication error occurred, but didn't hurt anyone, it's called a potential adverse drug event. Errors are caused by human factors, inadequate communication, or confusing labels, packaging, or drug names. MUST BE REPORTED Reduce errors by Medication reconciliation-process of comparing the medications a patient is taking and should be taking with newly ordered medications to identify and resolve discrepancies should occur anytime there is a change in site, or being discharged.
13. Compare and contrast prescription and over-the-counter drugs.
Prescription drugs: Drugs that may be additive or may be too harmful for self-administration, treat complex conditions, require skill to administer, and client must receive authorization to receive the drug. Advantages:Health care provider can examine and diagnosis client, maximize therapy, client teaching, client follow-up OTC: Do not require authorization from health care provider, clients may treat themselves, must carefully follow directions, no monitoring from health care provider needed. food for thought: With most illnesses (60% to 95%), initial therapy consists of self-care, including self-medication with an OTC drug OTC Risks: No drug without risks, may not choose proper medications, no assistance from health care provider, may interact with food, herbals, prescription, or other OTC drugs, may be ineffective or harmful
25. Describe the relationship between receptors and drug action
Receptor= target on the cell the drug is going for. Receptors are not made for drugs, drugs are made to fit into certain receptors on that target cell that we are looking to effect. Agonist enhances normal cellular function and antagonists block cellular activity. *drug never does something to us that we don't already do to ourselves Receptors can change based on a couple of things that can happen: has to do with saturation of the receptor sites continuous activation over time will cause cells to change their receptor site numbers available to those drugs and build a tolerance i.e. Narcotic addicts need more and more because of the tolerance effect continuous inhibition creates a hypersensitivity to that drug i.e. Beta-blocker: blocking sympathetic stimulation; if it is stopped, now the sympathetic stimulation will cause massive reaction due to previous inhibition down regulation: tolerance to these drugs binding to the receptors.
11. Categorize the four stages of new drug approval.
Stage 1: Preclinical testing=extensive lab testing; 1st on cultured human cells then on animals. Most drugs don't get past this stage because they are too toxic or ineffective Stage 2: Clinical investigation: phase trials -Phase 1= testing on 20-80 healthy volunteers, focus on safety -Phase 2= testing on several hundred with the disease, focus on effectiveness, may take several years -Phase 3= testing on large numbers of variable pts with the disease, drug-drug interactions examined, chronic conditions tested to determine safety, several years + thousands of pts; Stage 3: if drug shows promise then a New Drug Application is submitted to the FDA Stage 4: Postmarketing surveilance: surveys for harmful drug effects in a larger population, adverse effects reported
Relate a drug's therapeutic index to its margin of safety
TI= lethal dose / effective dose i.e. 100/10= 10 aka you would have to give someone 10x the normal dose to give them the lethal amount (very safe) i.e. 20/10= 2 aka you would have to give someone 2x the normal dose to give them the lethal amount (not very safe) The higher the therapeutic index, the safer the drug
Influences on Distribution
The ability to: 1 - travel to the site of action via the bloodstream; peripheral vascular or cardiac disease may delay medication distribution. 2 - leave the bloodstream by traveling between the capillaries' cells. Meds compete for protein-binding sites within bloodstream, primarily albumin. Ability to bind can affect how much of the med will leave and travel to target tissues. Two meds can compete for same binding sites, resulting in toxicity or decreased bioavailability. BARRIERS: meds that are lipid soluble or have a transport system can cross the blood-brain barrier or the placenta.
Identify major processes by which drugs are excreted
The elimination of drugs from the body: Kidneys (main organ) Liver Bowel Less common routes: lungs, sweat, salivary, mammary glands
Identify the significance of the dose-response relationship to clinical practice
The intensity of the drug and the response in terms of dose vs the percentage of responses **we would not have a flat graph curve means the concentrations are not really effecting that person (varying doses and the responses)
5. Define and delineate between a drug's therapeutic classification versus their pharmacologic classification
Therapeutic classification - What is being treated by the drug • Therapeutics is the usefulness in treating a specific disease. • Some may be placed in several therapeutic classes. • Pharmacologic classification - How the drug acts • Pharmacologic classification - The mechanism of the drug or how the drug produces its effects in the body - More specific than therapeutic classification - Requires understanding of biochemistry and physiology - May use drug's chemical name
20. Explain how a drug reaches and maintains its therapeutic range in the plasma
Therapeutic drug monitoring helps determine dose needed for peak level to occur in therapeutic range. Physicians will order peak and trough levels. (trough level drawn right before a dose is given) (peak level drawn after the dose is administered)
3. Using specific examples, explain the difference between the pharmacologic and therapeutic methods of classifying drugs.
Therapeutic: describes what is being treated by the drug Pharmacologic: describes how the drug acts i.e. T: antihypertensive, anticoagulant P: diuretic, vasodilator
27. Describe and differentiate how drug interactions can create the following outcomes: additive, synergistic, antagonistic, and unique responses.
When two drugs or a drug and another element have an effect on each other. This interaction may: Increase or decrease the therapeutic effect of the drugs. Create a new effect. Increase the incidence of an adverse effect= A usually undesirable effect other than the intended therapeutic effect. An additive effect occurs when two or more "like" drugs are combined. An additive effect may be intentional or may unintentionally cause harm. A synergistic effect occurs when two or more "unlike" drugs are used together to produce a combined effect Consider the following example: A beneficial synergistic effect occurs when two different types of antibiotics that work in very different ways are combined, such as penicillin G and an aminoglycoside antibiotic. An antagonistic drug interaction is the opposite of a synergistic effect. It results in a therapeutic effect that is less than the effect of either drug alone because the second drug either diminishes or cancels the effects of the first drug. Antagonistic interactions can also occur at receptor sites. Unusual and in fact may be the opposite of what is anticipated. Example: If the drug is supposed to make you tired, it makes you wide awake.
35. Describe physiological changes during pregnancy that may affect the absorption, distribution, metabolism, and excretion of drugs.
• Physiologic changes during pregnancy can alter normal pharmacokinetic responses. - Speeding up - Slowing down • Absorption - Increased levels of progesterone cause a decrease in gastric tone and intestinal motility, resulting in delayed gastric emptying. ▪Delayed gastric emptying results in extended absorption time for oral drugs. - High estrogen levels cause increased hydrochloric acid production. ▪May affect absorption of certain acid labile drugs - Progesterone increases pulmonary blood flow, respiratory tidal volume, and minute volume by 40%. ▪Respiratory agents may be absorbed in larger quantities. ▪Higher serum drug levels • Distribution - Affected during pregnancy by changes in total body water, which may increase by over 50%. ▪Leads to greater hemodilution of plasma proteins and drugs - When plasma proteins are diluted, fewer are available to bind with drugs. ▪Higher concentration of "free" drug in the plasma ▪More drug molecules available to transfer across the placenta - Highly lipophilic drugs are distributed into lipid-rich breast milk. - Maternal heart rate may increase up to 15 beats a minute leading to greater drug distribution. • Metabolism - Significantly altered by pregnancy - Cytochrome P450 enzymes increase, noticeably CYP2D6 and CYP3A4 - CYP1A2 decreases ▪Providers should use caution when prescribing any drug during this time ▪Limit prescriptions to drugs with low-risk safety profiles • Excretion - Enhanced during pregnancy ▪Increased renal plasma flow ▪Increased glomerular filtration rate ▪Decreases in blood urea nitrogen (BUN) and creatinine levels - Results in increased renal elimination of drugs - Dosage of many medications must be adjusted
16. Define and delineate between a drugs' chemical, generic, and trade names.
• Trade name - Name given by the pharmaceutical company marketing the drug - Attempt to be short and easy to remember - Proprietary • Generic drugs - Usually less expensive than trade-name drugs - Drug formulations may be different. - Inert and/or active ingredients may be same or different. ▪ This can change the bioavailability. - Defined as the rate and extent to which the active ingredients are absorbed from a drug product and then available at the site of action *Chemical names -are typically very long and too complex to be commonly used in referring to a drug in speech or in prose documents.[1] For example, "1- (isopropylamino)-3-(1-naphthyloxy) propan-2-ol" is a chemical name for propranolol.
