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pharm 3304 test1
Question | Answer |
---|---|
drug | Any chemical that can affect living processes |
pharmacology | Study of drugs and their interactions with living systems |
clinical pharmacology | Study of drugs in humans |
therapeutics | The use of drugs to diagnose, prevent, or treat disease or to prevent pregnancy, or more simply: the medical use of drugs |
10 important characteristics of a drug | effectiveness, safety, selectivity, Reversible action Predictability Ease of administration Freedom from drug interactions Low cost Chemical stability Simple generic name |
effectiveness | a drug that elicits the responses for which it is given, most important property a drug can have-not effective-not prescribed |
safety | a drug that cannot produce harmful effects, even it administered at high doses and for a very long time, there is no such thing as a safe drug |
selectivity | a drug that elicits only the response for which it is given and would not produce side effects--there is no such things as a selective drug: all medications cause side effects |
reversible action | it is important that effects be reversible; in most cases, we want the drug to subside within an appropriate time |
predictability | it would be helpful if, prior to drug administration, we could know with certainty just how a given patient will respond |
ease of administration | simple to administer: route would be convenient, and the number of doses per day would also be low. This in turn can: enhance adherence, and decrease administration errors |
freedom from drug interactions | drugs can interact when a patient is taking more than two drugs at one time; these interactions can either augment or reduce drug responses |
low cost | the ideal drug would be easy to afford |
chemical stability | effectiveness of drug can be lost during storage or when put into solution |
simple generic name | generic names of drugs are usually complex, and difficult to remember and pronounce; the ideal drug should have a generic name that is easy to recall and pronounce |
the nurse must know | Appropriate medications for the patient, What drugs are contraindicated, probable consequences of the interaction between drug and patient, Correct administration, Therapeutic objective is to provide maximum benefit with minimal harm |
nurse's role as advocate | Follows the patient’s status most closely First member of the health care team to observe and evaluate drug responses and intervene if required Must know the response that a medication is likely to elicit Last line of defense for the patient |
four phases of new drug development | Preclinical testing Clinical testing Phase 1: healthy subjects Phase 2: target group Phase 3: larger target group Phase 4: FDA evaluation and postmarketing surveillance |
drug names | chemical, generic, and trade |
chemical name of a drug | name which constitutes a description of a drug using the nomenclature of chemistry |
generic name of a drug | name of drug assigned by the United States Adopted Names Council, each drug only has one generic name, also known as the nonproprietary name |
trade name of drug | proprietary or brand name, under which a drug is marketed--more than one per drug |
pharmacokinetic processes | absorption, distribution, metabolism, and excretion |
absorption | transfer of drug from site of administration to the blood Influenced by: rate of dissolution surface area blood flow lipid solubility |
distribution | drug movement from the blood to the interstitial space of tissues and from there into cells |
metabolism | enzymatically mediated alteration of drug structure;conversion of drug into less active products that are more easily excreted Primary site: liver – P450 enzyme system. A system of 12 closely related enzyme families |
excretion | movement of drugs and their metabolites out of the body, organ used: kidneys |
Parenteral | into the blood or tissue, Intravenous (quickest and irreversible), intramuscular, subcutaneous |
Enteral | oral: Route most commonly used Safe, slow drug action May be affected by food; “first pass” effect Tablets, enteric coated, sustained release |
GI tubes | Used in patients who cannot take oral medications PEG (percutaneous endoscopic gastrostomy) Higher risk of complications |
Other routes of administration | Topical – to treat local area Transdermal – absorbed into bloodstream Inhalation Sublingual Via vagina Via rectum |
blood brain barrier BBB | Tight junctions between the cells that compose the walls of most capillaries in the CNS Only drugs that are lipid soluble or have a transport system can cross the BBB to a significant degree |
placental drug transfer | Membranes of the placenta do NOT constitute an absolute barrier to the passage of drugs |
protein binding | Drugs can form reversible bonds with various proteins. Plasma albumin is the most abundant and important. Large molecule that always remains in the bloodstream Impacts drug distribution |
special considerations in drug metabolism | Induction of enzymes – liver makes drug metabolizing enzymes First pass effect Nutritional status – malnutrition reduces metabolisim Competition between drugs – drugs metabolized by same pathway -> less metabolism Genetics |
First pass effect | when oral drugs are absorbed into the GI tract, they are carried directly to the liver by hepatic portal vein; if the capacity of the liver to metabolize a drug is extremely high, that drug can be completely inactivated on its first pass through the liver |
age and metabolism of drugs | During the time prior to hepatic maturation, infants are especially sensitive to drugs--inability to metabolize drugs because of immaturity of liver |
induction of drug metabolizing enzymes | some drugs act on liver and increase rates of drug metabolism |
nutritional status | hepatic drug-metabolizing enzymes require a number of cofactors to function. In the malnourished patient, these cofactors may be deficient, causing drug metabolism to be compromised |
competition between drugs | 2 drugs metabolized via the same pathway, may compete with other for metabolism, one may rise to dangerous levels if metabolism is depressed |
half life of a drug | time required for the amount of drug in the body to decrease by 50% |
significance of half life of a drug | Affects duration of action; Drugs with short half life must be administered more frequently. Drug with a long half life, it may be necessary to administer a loading dose. When drug administered repeatedly, levels will rise and reach a steady plateau. |
kidney | most important organ for drug excretion |
drug receptor interaction | Drugs exert effects by binding to receptors on cell surfaces. Receptors: proteins on or in cells that interact with drug molecules. Number and sensitivity of receptors affects drug action Number and sensitivity of receptors can change |
lock and key concept | Think of receptors and drug molecules as locks and keys. Drug molecule (key) binds to the receptor (fits in the lock). Drug molecule (key) causes a physiologic response (lock opens). |
affinity | refers to the strength of the attraction between a drug and its receptor, drugs with high affinity are administered at low doses |
intrinsic | refers to the ability of a drug to activate the receptor following binding, high intrinsic ability equal intense receptor activation |
agonist | a drug that combines with a receptor and initiates a pharmacologic response; a drug with affinity and efficacy |
efficacy | A drug’s ability to initiate biological activity as a result of binding with a given receptor. (key opens lock) |
antagonist | drug that combines with a receptor and inhibits or counteracts effects caused by other drugs or cellular components |
partial agonist | acts with moderate intrinsic activity May act as agonist and antagonist |
consequences of drug-drug interactions | Intensification of effects Increased therapeutic effects Increased adverse effects Reduction of effects Reduced therapeutic effects Reduced adverse effects Creation of a unique response |
impact of food on drug absorption | Impact of food on: Drug absorption Decreased absorption Increased absorption |
Grapefruit Juice | Inhibits the metabolism of certain drugs Raises the drugs’ blood levels 406% increase of felodipine Others – lovastatin, cyclosporine, midazolam, etc. |
five causes of medication errors | Human factors: performance deficits; knowledge deficits; miscalculation; Communication mistakes:oral and written orders; Name confusion: sound alike, look alike drugs; Packaging, formulations, delivery devices Labeling and reference materials |
ways to reduce medication errors | Help and encourage patients and their families to be active, informed members of the health care team. Create an institutional culture dedicated to safety. |
ways to reduce medication errors (2) | Give health care providers the tools and information they need to prescribe, dispense, and administer drugs as safely as possible. Institute safety checklists for high-alert drugs. |
ways to reduce medication errors (3) | Replace handwritten medication orders with a computerized order entry system. Have a senior clinical pharmacist accompany physicians on rounds. Use a bar-code system. Do not use error-prone abbreviations or symbols. |
side effect | a nearly unavoidable secondary drug effect produced at therapeutic dosesMay develop soon after drug initiated or not until drug has been taken for weeks or months |
toxicity | an adverse drug reaction caused by excessive dosing |
allergic reaction | an immune response; for an allergic reaction to occur, there must be prior sensitization of the immune system; can range from mild rash to anaphylaxis |
idiosyncratic effect | An uncommon drug response resulting from a genetic predisposition Overresponse Underresponse Paradoxical |
iatrogenic disease | Sometimes also called drug-induced disease Essentially identical to naturally occurring pathology |
physical dependence | Develops during long-term use of certain drugs A state in which the body goes through withdrawal if the drug use is discontinued Important to warn patients against abrupt discontinuation of any medication without first consulting a health professional |
carcinogenic effect | Only a few therapeutic agents are carcinogenic. Several drugs used to treat cancer are among those with the greatest carcinogenic potential. |
teratogenic effect | A drug-induced birth defect |
complementary and alternative therapies | treatment practices that cannot be widely accepted or practiced by mainstream clinicians in a given culture |
role of the professional nurse regarding complementary and alternative therapies. | Safety, Teaching, and Serve as Resource |
black cohosh | menopause; gastrointestinal symptoms, rash headache, dizziness, weight gain, and cramps; rarely associated with liver toxicity |
cranberry juice | prevent UTI; drinking more than 1 L/day may increase the risk of GI upset and formation of uric acid kidney stones |
echinacea | strengthen immune system; unpleasant taste, rare: fever, nausea, vomiting, allergic reaction; long term exposure can suppress immune system |
feverfew | prevent migraines; abdominal pain, indigestion, diarrhea, flatulence, nausea, vomiting; can decrease platelet aggregation and increase chance of bleeding |
garlic | CV system, reduce triglycerides, lower BP; unpleasant taste, bad breath, GI irritation |
ginger | suppress nausea and vomiting, motion sickness; may have potential to cause CNS depression and cardiac dysrhythmias, GI disturbances, may stimulate uterus during pregnancy |
Ginkgo biloba | memory, research lacking; may cause upset stomach, headache, dizziness, or vertigo, some reports of spontaneous bleeding |
glucosamine | osteoarthritis; GI disturbances, nausea, heart burn, caution should be used if allergic to shellfish |
probiotics | beneficial bacteria; flatulence and bloating, infection of blood in severely ill immunocompromised patients taking broad spectrum antibiotic long term |
saw palmetto | benign prostatic hypertropy; may cause nausea or headache, may cause fetal birth defects |
St. John's wort | depression; interacts with many drugs, and increases metabolism of drugs; may cause allergic reactions, CNS effects, GI discomfort, fatigue, dry mouth, and headache, may cause phototoxicity |
valerian | promote sleep; daytime drowsiness, dizziness, depression, dyspepsia, pruritus, prolonged use may cause headache, nervousness, or cardiac abnormalities; should be avoided by pregnant or breastfeeding women. |
comfrey | medicinal herb used orally and topically, topical is safe; oral is not safe and can cause hepatic VOD (veno-occlusive disease) which can result in severe liver damage; may be carcinogenic |
kava | anxiety, promote sleep, and relax muscles; can cause severe liver damage; hepatoxicity leading to liver failure and need of transplant |
Ma Huang (ephedra) | elevate blood pressure and stimulate heart and CNS; associated with stroke, myocardial infarction, and death |
Food Drug and Cosmetic Act 1938 | Targeted safety and efficacy Regulated manufacture, distribution, advertising, labeling Made USP official standard for strength and purity |
Harris Kefauver Amendment | First law to demand that drugs actually offer some benefit |
Comprehensive Drug Abuse Prevention and Control Act (1970) | Called Controlled Substances Act Classified and regulated drugs with potential for abuse Established drug abuse education and treatment programs |
Schedules of Abuse Potential | 1: high abuse potential, no approved medical use 2: high abuse potential, accepted medical use 3: less abuse potential, accepted medical use 4: some abuse potential, accepted medical use 5: less abuse potential than schedule 4, accepted medical use |
1992 Rx Drug User Fee Act | Shortened review process |
1997 FDA Modernization Act | Permitted drug companies to provide information about non-FDA approved uses ( off-label uses) |
DSHEA (1994) | Dietary Supplement Health and Education Act of 1994, regulates botanical products (medicinal herbs), vitamins, and minerals--it exempts these products from meaningful FDA regulations |
DSHEA and Adverse Effects | a product is presumed safe until proven hazardous; burden of proving a product dangerous lies with the consumer and the FDA |
DSHEA and Package Labeling | all herbal products must be labeled as "dietary supplements;" the label cannot claim the product can be used to diagnose, prevent, treat, or cure a disease. Must read: This product is not intended to diagnose, treat, cure, or prevent any disease. |
DSHEA and Impurities, Adulterants, and Variability | does not address the issues of impurities, adulterants, or variability; therefore dangerous products have been allowed to reach consumers; however Current Good Manufacturing Practice ruling fixes this |
Current Good Manufacturing Practices Ruling (CGMP's) 2007 | Ensures that dietary supplements be devoid of adulterants, contaminants, and impurities and that the package labels accurately reflect the identity, purity, and quality and strength of what's inside. Label should indicate active and inactive ingredients. |
National Center for Complimentary and Alternative Medicine (NCCAM) | charged with promoting and funding basic research and clinical trials designed to address open questions on the safety and efficacy of CAM; created by National Institutes of Health |
Six Rights | Right patient, right drug, right dose, right route, right time, and right documentation |