pharm quiz 1
scheduled drugs level 2
Used therapeutically with prescription High abuse, dependence Morphine, PCP, cocaine, methadone methamphetamine
first pass effect
When oral drugs are absorbed from the GI tract they are carried directly to the liver via the hepatic portal vein. Some drugs can be inactivated on 'first pass'
clinical testing Phase II
500 to 5000 patients Of these only a few hundred take for more than 3 to 6 months. Patients with condition drug designed for Therapeutic utility and dosage range
1. A nurse is preparing to administer medications. Which patient would the nurse consider to have the greatest predisposition to an adverse reaction? a. A 30-year-old male with kidney disease b. A 75-year-old female with cystitis c. A 50-year-old male with an upper respiratory tract infection d. A 9-year-old child with an ear infection
1. ANS: A The individual with impaired kidney function will be at risk of having this drug accumulate to a toxic level due to potential excretion difficulties. Cystitis is an infection of the bladder and not usually the cause of excretion problems that might lead to an adverse reaction from a medication. A respiratory tract infection would not predispose a patient to an adverse reaction, because drugs are not metabolized or excreted by the lungs. A 9-year-old child would not have the "greatest" predisposition to an adverse reaction simply because he is a child; nor does an ear infection put him at greater risk.
Alternative
herbs, vitamins, supplements
Pharmacokinetics
how the body handles medication
Succinylcholine
induced paralysis Usually brief May last for hours in genetically predisposed patient (idiosyncratic effect)
intravenous absorption
instant and complete
Biologics:
manufactured in a living system
IM and subcutaneous adsorption
may be fast or slow Water soluble absorb quicker Blood flow to area
QT interval
measure of the time required for the ventricles to repolarize after each contraction
Medication Errors
"any preventable event that may cause or lead to inappropriate medication use or patient harm, while the medication is in the control of the healthcare professional, patient, or consumer. Such events may be related to professional practice, healthcare products, procedures, and systems, including prescribing; order communication, product labeling, packaging and nomenclature, compounding, dispensing; distribution, administration; education, monitoring; and use"
Iatrogenic disease
'a disease produced by a physician," also used to refer to a disease produced by drugs (for example, drugs for antipsychotic disorders can cause Parkinson's-like symptoms) Sometimes also called drug-induced disease Essentially identical to naturally occurring pathology
Preclinical Trials
(in animals) May take 1 to 5 years Toxicity Pharmacokinetics Possible Useful Effects
2. A nurse on a busy orthopedic unit is preparing to administer morning medications. Which aspect of the assessment would be most important prior to the administration of an antihypertensive agent PO? a. Early signs that an adverse reaction is occurring b. Route by which the drug is to be administered c. Patient's blood pressure prior to administration d. Patient beginning complaints of a headache
2. ANS: C Blood pressure measurement is imperative prior to the administration of an antihypertensive agent to prevent potential life-threatening complications. The nurse cannot determine early signs of an adverse reaction if the medication has not yet been administered. The route by which the drug is administered is not a priority in this question, because there is no indication the patient is having difficulty swallowing. The patient's beginning complaints of a headache may be indicative of hypertension, which would be validated by taking the blood pressure, the priority assessment.
3. A nurse educator is providing a continuing education class on pharmacology. To evaluate the learning of the nurses in the class, the nurse educator asks, "Which drug name is a generic drug name?" a. Acetaminophen b. Tylenol c. Cipro d. Motrin
3. ANS: A Acetaminophen is the generic name. Tylenol, Cipro, and Motrin are all trade names.
4. A nurse is reviewing the six rights of medication administration. Which medication order is written correctly? a. Regular insulin 10 units SubQ q AM b. Regular insulin 10U subQ q AM c. Regular insulin 10 units SQ q AM d. Regular insulin 10.0 units subQ q AM
4. ANS: A Regular insulin 10 units SubQ q AM is correct, because it uses correct and approved abbreviations. Units should be written out; the use of "U" is incorrect, because it is an unapproved abbreviation. SQ is not an approved abbreviation; SubQ should be used instead. The use of a trailing zero is no longer approved; 10.0 should be written as 10.
5. A prescriber has ordered a placebo for a patient. Which statement would most accurately reflect the placebo effect of medications? a. A placebo effect is caused by psychological factors rather than physiological ones. b. When a placebo effect occurs, it indicates that the patient did not have an illness. c. A placebo effect is a rare effect seen only with psychotropic medications. d. A placebo effect is almost always a positive response that facilitates healing.
5. ANS: A A placebo effect is caused by psychological factors, not physiological factors. A placebo effect does not determine whether a patient has an illness. A placebo is ordered for various reasons; each is individualized and not for specific classifications of drugs only. A placebo effect may or may not be positive, depending on what the patient believes is the effect on the body.
Teratogenic effect
A drug-induced birth defect
Side effect
A nearly unavoidable secondary drug effect produced at therapeutic doses May develop soon after drug initiated or not until drug has been taken for weeks or months
oral disadvantages
Absorption variables Can be inactivation Pt must be conscious and cooperative
Consequence of Metabolism
Accelerated Renal Drug excretion Drug Inactivation Increased Therapeutic Action Activation of pro-drugs Pharmacologically inactive as administered and then undergoes conversion to active form Increased or Decreased toxicity
ionization
Acids ionize in bases Bases ionize in acids We do not want ionized substances as they will not cross
Special Considerations for metabolism
Age - metabolize limited in infant First-Pass Effect These drugs are given IV to bypass liver and go directly to site Nutritional Status Malnutrition can impede metabolism in liver Competition between drugs
Idiosyncratic effect
An uncommon drug response resulting from a genetic predisposition
Adverse Drug Reactions
Any noxious, unintended, and undesired effect that occurs at normal drug doses Excludes excessive dosages Can range from annoying to life-threatening Most common in the elderly and very young Risk increased by severe illness
intravenous advantages
Rapid onset Precise control Can give large fluid amounts Some irritant drugs can only be given IV
distribution effected by
Blood flow to tissue Ability to Exit the vascular system: protein binding, blood brain barrier Ability to Enter cells
IM and subcutaneous advantages
Can be used for poorly soluble drugs Depot preparation (prepared so it is absorb slowly over time)
IM and Subcutaneous Barriers
Capillary wall
Three (3) ways to cross a membrane
Channels or pores Small ions (sodium and potassium) Use of a transport system Direct penetration of the membrane Lipid soluble drugs
3 checks for medication
Check MAR Check drug 3 times (preparing, pouring, taking it out of unit-dose container or connecting to IV tubing Check drug before giving to patient
QT drug problems
Creates serious risk of life-threatening dysrhythmias Do not use two QT drugs concurrently.
steps of pharmacokinetics
Cross membranes Absorption (taken into body) Distribution (moved into various tissues) Metabolism (changed into a form that can be excreted) Excretion (removed from the body) Drug Response Time
metabolism
Enzymatic alteration of drug structure Most drugs metabolized in liver
Physical dependence
Develops during long-term use of certain drugs (opioids, alcohol, barbiturates, and amphetamines) A state in which the body has adapted to drug exposure in such a way that: An abstinence syndrome will result if the drug use is discontinued
Identifying Adverse Drug Reactions
Did symptoms appear shortly after the drug was first used? Did symptoms abate when the drug was discontinued? Did symptoms reappear when the drug was reinstituted? Is the illness itself sufficient to explain the event? Are other drugs in the regimen sufficient to explain the event?
IM and subcutaneous disadvantages
Discomfort Inconvenience
Maintenance dose
Doses to keep blood level therapeutic
oral advantages
Easy Convenient Inexpensive Safer than injection
Excretion steps
Glomerular filtration Passive reabsorption Active tubular secretion
intravenous disadvantages
High cost Expertise required Irreversible Risk of fluid overload Infection embolism (air bubble)
scheduled drugs level 1
Highest potential for abuse Limited to no therapeutic use Heroin, LSD, marijuana
oral absorption
Highly variable
Allergic reaction
Immune response Determined primarily by the degree of sensitization of the immune system - not by drug dosage Patient's sensitivity to a drug can change over time Very few drugs cause severe allergic reaction Penicillins are the most common Allergies may also be induced by sulfonamides (diuretics, antibiotics, and oral hypoglycemic agents)
liver failure signs... educate patient:
Jaundice, dark urine, light-colored stools, nausea, vomiting, malaise, abdominal discomfort, loss of appetite
clinical testing Phase III
Large numbers of patients Safety and Effectiveness
Hepatotoxic Drugs
Leading cause of liver failure in the U.S. As some drugs undergo metabolism, they are converted to toxic products that can injure liver cells. Monitor AST and ALT for liver injury.
oral administration barriers
Lining of GI system Capillary Wall
What crosses most easily
Lipid soluble, non-polar and non-ionized "like dissolves like"
scheduled drugs level 4
Lower, abuse, dependence Used therapeutically with prescription Diazepam, alprazolam
scheduled drugs level 5
Lowest dependence, abuse Used therapeutically without prescription OTC cough medicines with codeine
Organ-specific toxicity
Many drugs are toxic to specific organs.
scheduled drugs level 3
Moderate abuse, dependence High psychological dependence Used therapeutically with prescription Anabolic steroids, codeine, hydrocodone, some barbiturates
Absorption
Movement of drug from site of administration into the blood
Distribution
Movement of drugs throughout the body
Factors affecting absorption
Must be dissolved first Surface Area: larger absorbs faster Blood Flow Lipid Solubility Ph partitioning
Clinical testing (in humans) Phase I
Normal healthy volunteers Metabolism and biologic effects
Loading dose
One or two doses to get blood level therapeutic
Carcinogenic effect
Only a few therapeutic agents are carcinogenic. Several drugs used to treat cancer are among those with the greatest carcinogenic potential. Evaluating drugs is difficult - may take decades for evidence of carcinogenesis after exposure.
Addiction
Overwhelming feelings that drives someone to use drug repeatedly
Dependence
Physiological or psychological need for a substance
Ways to Minimize Adverse Drug Reactions
Prescriber - Select the least harmful drug. Balance potential risks versus probable benefit. Nurse - Evaluate patient for ADRs and educate patients and families on how to minimize harm. Patients and families - Watch for signs an ADR may be developing and notify health care provider.
clinical testing Phase IV
Released for use in general population Adverse reaction reporting largely voluntary
Severe reactions (potentially fatal)
Respiratory depression, neutropenia, hepatocellular injury, anaphylaxis, hemorrhage
6 Rights of medication
Right client Right med Right dose Right route Right time Right documentation
Safety
Safe drug is one that cannot produce harmful effect even in high doses (no such thing as safe drug)
Mild reactions
Scope of the problem Drowsiness, nausea, itching, and rash
Clinical Pharmacology
Study of drugs in humans
Oral administration
Tablets Enteric-Coated Sustained-release
Toxicity
adverse drug reaction caused by excessive dosing May occur even with normal dosing Neutropenia (risk for infection) and anticancer medications
Drug
any chemical that can effect living process
Traditional drugs
based on tradition and clinical trials
Intravenous barriers
none
Selectivity
produces only effect for which it is given
Effectiveness
produces the response for which it was given
excretion
removal of drugs from the body
Pharmacology
study of drugs and their interactions with living systems
QT drugs
the ability of some drugs to prolong the QT interval on ECG
Therapeutics
use of drugs to diagnose, treat, or prevent disease or to prevent pregnancy
QT drug high risk patients
women, the elderly, and patients with bradycardia, CHF, congenital QT prolongation, low potassium, and low magnesium