Pharmacology Exam 1

Why do nurses need to know about pharmacology?

Why do nurses need to know about pharmacology?

-nursing is the final screen to discover a mistake someone else made

-administering medications safely

-gain respect from peers and providers through and advanced knowledge of pharmacology

-knowledge of medications promotes best outcomes for your patient

what are the 5 key patient rights?

-right patient, right dose, right time, right route, right drug

what are the other patient rights (3)?

-right storage

-right preparation

-right recording

What are the pregnancy risks associated with medication?

-category A

-category B

-category C

-category D

-category X

*remember, fetal risk goes from less risk to most risk for A (less) to X (more)

What is a pregnancy category A drug?

Adequate studies in pregnant women have NOT demonstrated a risk to the fetus in the first trimester or later trimesters

What is a pregnancy category B drug?

Animal studies have not demonstrated a risk to the fetus, but there are no adequate studies in pregnant women, studies have no demonstrated a risk to the fetus during the 1st trimester or later trimesters

What is a pregnancy category C drug?

Animal studies HAVE shown an adverse effect on the fetus, but there are no adequate studies in humans, the benefits from the use of the use of the drug in pregnant women may be acceptable despite its potential risks

What is a pregnancy category D drug?

There is evidence of human fetal risk, but the potential benefits from the use of the drug in pregnant women may be acceptable despite its potential risks

what is a pregnancy category X drug?

Studies in animals/humans demonstrate fetal abnormalities/adverse reactions, reports indicate evidence of fetal risk. This risk of use in a pregnant woman clearly outweighs any possible benefit

What is an important rule to remember when taking medications and pregnant?

Regardless of the designated pregnancy category or presumed safety, no drug should be administered during pregnancy unless it is clearly needed

Teratogenic

causing adverse effects/harm to the fetus

What are the nursing process and drug administration phases?

-Assessment

-Diagnosis

-Planning

-Implementation

-Evaluation

Assessment phase includes:

information gathering or patient, past history, physical exam, vitals

diagnosis phase includes:

statement of actual/potential problem based on assessment

Planning phase includes:

developing goals and desired outcomes for patient

implementation phase includes:

actions taken

Ex.) administration of drugs

evaluation phase includes:

Determining effects of the intervention

nursing process

problem solving process used to provide efficient nursing care, it involves gathering information, formulating a nursing diagnosis statement, prioritizing the diagnoses, developing goals and desired outcomes for the patient, carrying out interventions, and evaluating the process

Why is the evaluation phase important?

To ensure therapeutic response, occurrence of adverse drug affects, occurrence of drug-drug, drug-food, drug-alernative therapy, or drug-laboratory interactions

-may lead to changes in nursing interventions being used to provide better and safer patient care

What are the priority actions for the nurse to take in the event of a medication error?

-stop drug

-assess the patient (ABCs)

-give epinephrine if needed quickly: IV is quickest if not IM

-give fluid, oxygen, antidote

-notify the provider

PREVENTION is best!

What are the signs of anaphylactic shock?

-shortness of breath (SOB)

-wheezing

-blood pressure changes: may be high initially, then low

-rash/itching

-tachycardia, severe anxiousness

-dilated pupils (miosis)

teaching about medications during each administration is important because?

Patients are becoming more responsible for their own care, it is essential that they have all the information necessary to ensure safe & effective drug therapy at home

what is the danger or crushing an extended release medication?

-medication is designed to dissolve in the pH of the small intestine (increased stomach pH)

-early release can cause dangerously high concentration to quickly

-increased risk of toxicity

Schedule I medication

High abuse potential and NO accepted medical use

(Heroin, marijuana, LSD)

Schedule II medication

high abuse potential with severe dependence liability (narcotics, amphetamines, and barbiturates)

Schedule III medication

less abuse potential than schedule II drugs and moderate dependence liability (non-barbiturate sedatives, non amphetamine stimulants, limited amounts of certain narcotics)

Schedule IV medication

less abuse potential than schedule III and limited dependence liability (some sedatives, anti-anxiety meds, and non-narcotic analgesics)

Schedule V medication

limited abuse potential primarily small amounts of narcotics like codeine must be 18 years of age or older to purchase, may be purchased without a prescription

What are reliable sources for drug administration?

Drug label & insert, reference books: physicians drug reference (PDR), drug facts and comparisons, AMA drug evaluations, Lippincott’s nursing drug guide (LNDG), textbook, peer reviewing journals: CDC, drugs.com, NIH, ADA, mayoclinic, nursing central, and epocrates

What does drug half-life mean?

The time it takes for the amount of drug in the body to decreases to one-half of the peak level

How do you determine a drug half-life?

Patient takes 20mg of a drug with a half life of 2 hours, in 2 hours 10 mg of the drug will remain, 2 more hours 5 mg of the drug will remain

What are the 4 stages of pharmokinetics?

-Absorption

-Distribution

-Metabolism

-Excretion

pharmacokinetics phase 1: absorption

what happens to a drug from the time it is introduced to the body until it reaches the circulating fluids

pharmacokinetics phase 2: distribution

the movement of a drug to the site of action by bodily fluids

Pharmacokinetics phase 3: metabolism AKA biotransformation

-breaks down medications and makes them

-helps prevent medications from causing adverse effects on the body

What is the single most important site of metabolism?

The liver

Pharmacokinetics phase 4: excretion

Removal of drugs from the body

What plays the most important role in excretion of medication?

The kidneys

P450 cytochrome

class of enzymes the liver uses to alter the drug and start biotransformation/metabolism

What are the 2 most commonly used p450 enzymes?

-CYP3A4

-CYP2D6

What is the interaction between grapefruit juice and metabolism of drugs?

Grapefruit juice has been found to affect liver enzyme systems for up to 48 hours after it has been ingested

-this can result in increased/decreased serum levels of certain drugs

-inhibits CYP3A4 buy decreasing the intestinal metabolism of many drugs

What drug specifically states to not be combined with grapefruit juice ?

atorvastatin

Peak of medication

1 1/2 hours after administration, highest therapeutic level of medication

“That’s high enough we’re getting toxic”

Trough of medication

Draw 30 minutes prior to the next dose to determine when to administer next dose, lowest therapeutic level of medication

“Time for another dose”

Which route provides the best and fastest absorption?

Intravenous (IV)

What can happen when two highly protein drugs are given together?

When two high protein drugs are given together they compete for protein binding sites causing free drug to be released into circulation, increasing concentration

What are some of the effects of combining two highly protein drugs?

-drug accumulation and possible drug toxicity

-low serum protein levels decrease the amount of protein binding sites and can increase the amount of free drug in circulation

-drug dose is prescribed according to the % of which the drug binds to protein

-IT WILL CAUSE TOXICITY

What are the signs and symptoms of renal insufficiency ?

-decreased urine output

-fluid retention

-irregular heart beat

-fatigue

-confusion

-shortness of breath

-nausea

What labs should you monitor for renal insufficiency?

-creatinine

-GFR

-BUN

Creatinine normal values

.8 - 1.4 mg/dl

GFR normal values

above 60 ml/min

BUN normal values

7 - 20 mg/dl

What are the signs and symptoms of liver failure?

-jaundice

-ascites

-nausea

-vomiting

-pain in the upper right quadrant

-malaise

-confusion

What labs should you monitor for liver failure?

-increased ALT (alanine transaminanse)

-increased AST (aspartame transaminase)

-labs will be ELEVATED showing inflamed/injured liver cells

-also look at liver function tests (platelets and coagulation factors)

“Free drug”

active drug

Pharmacogenetics

how drugs affect a person depending on their genetics

Substrate

The drug being metabolized

Inducer

increase activity, raises levels of enzymes

Inhibitor

decrease activity, reduces the levels of enzymes; can be strong, moderate, and weak

P450 system

liver enzymes used to metabolize drugs

-CYP3A4

-CYP2D6

Pharmacodynamics

The science of dealing with interactions between living organisms and foreign chemicals

Agonist

molecules that activate receptors

-MAKE THE CELL DO SOMETHING

What is an example of an agonist?

Activates certain receptors in the brain (endorphins)

(Serotonin)

Antagonists

PREVENT receptor activity

Noncompetitive antagonists

reduce the maximal response by reducing the number of receptors available for activation (ketamine)

Competitive antagonists

Compete with agonist at site, by binding reversible to the receptors

Ex.) fentanyl overdose, narcan is the agonist

order of renin angiotensin-aldosterone system (RAAS)

1: when BP falls (systolic 100mmHg or lower) kidneys release enzyme renin into blood

2: liver produces angiotensinogen

3: activation of angiotensin I to angiotensin II occurs in pulmonary capillary bed by converting enzyme

4: angiotensin II- powerful vasoconstrictor

5: angiotensin II becomes angiotensin III causes release of aldosterone from adrenal cortex

6: aldosterone causes increased sodium and water reabsorption by the tubules of the kidney

What are the results of the renin- angiotensin aldosterone system (RAAS)?

-increased blood volume

-increased sodium retention

-ADH release and water retention to increase blood volume

COMPENSATORY MECHANISM TO HELP ENSURE BLOOD FLOW IN MAINTAINED

Idiosyncratic reaction

Abnormal drug response (peculiar reaction) that is usually genetically related or due to an immunologic reaction

Serum creatinine

0.6 - 1.2 mg/dl

HIGH levels=kidney damage

WBC

4 - 11 mL/dL

ELEVATED=infection

ALT/AST

High levels-liver damage

Cd4 count

Used to monitor response to HIV meds

Many antibiotics damage?

Kidneys

Aminoglycosides basic action

inhibits protein synthesis in susceptible strains of GRAM NEGATIVE bacteria causing cell death

Aminoglycosides adverse effects

Ototoxicity, renal toxicity, GI disturbances, bone marrow depressions, and superinfections

Aminoglycosides pertinent nursing information

monitor for ototoxicity and nephrotoxicity

-encourage larger amounts of water to decrease nephrotoxicity

What are Aminoglycosides used for?

Treatment of serious infections caused by susceptible bacteria

What are common Aminoglycosides medications?

-MYCIN

-gentamicin

-streptomycin

-tobramycin

Carbapenems basic action

Inhibit cell membrane synthesis in susceptible bacteria, leading to cell death

-broad spectrum antibiotic effect against BOTH gram negative and gram positive bacteria

Carbapenems adverse effects

GI effects, diarrhea, C.diff, nausea, vomiting, headache, dizziness, superinfections

Carbapenems pertinent nursing information

Risk of infections related to loss of normal flora, acute pain related to GI/CNS affects of the drug, dehydration

-beta lactating ring can be destroyed by penicillinase

what are common Carbapenems medications?

-ertapenem (Invanz)

-doripenem (doribax)

-impenem- cilastatin (primaxin)

-meropenem (merrem IV)

Cephalosporins basic action

effective against a wide range of bacteria (beta lactam)

-with each generation comes an increase in attacking gram negative bacteria and crossing the blood brain barrier

Cephalosporins adverse effects

GI, nephrotoxicity especially if given with Aminoglycosides, adding anticoagulants may increase bleeding, no ETOH due to possible disulfiram effect

Cephalosporins common medications

multiple suffixes

-cephalexin, cefaclor, cefoxitin, cefdinir, certriaxone

Cephalosporins pertinent nursing information

With each generation comes an INCREASE in attacking gram negative bacteria

Fluoroquinolones basic action

interferes with DNA replication in susceptible gram,-negative bacteria, preventing cell reproduction

Fluroquinolones adverse effects

-Achilles or other tendon rupture/tendinitis (esp over age 60), colitis, nephrotoxicity, phlebitis at IV site

Fluoroquinolones pertinent nursing information

-adding Aminoglycosides, theophylline’s steroids increases toxicity

-watch when combining with cardiology meds!!! Can elevate QT level

-used for more serious infections and pateints who may be immunocompromised (HIV+)

Penicillin basic action

treat a broad spectrum of infections from bacteria

-produce bactericidal effects by interfering with the inability of susceptible bacteria to build their cell walls when they are dividing

-prevent bacteria from biosynthesizing the framework of the cell wall, & bacteria with weakened cell walls swell and then burst

Penicillin adverse effects

-(Amoxicillin) class 1 allergic response most common with PCNs has a beta lactam ring that can be destroyed by

-Augmentin is penicillin but also has clavulanic acid to protect beta lactum rings

What is augmentin often prescribed for?

Stubborn upper respiratory tract infections that are resistant to penicillin because clavaunic acid protects beta lactam antibiotics from being broken down by penicillinase

How do you treat an allergic reaction?

Give epinephrine

Pertinent nursing information for penicillin

monitor patient for sensitivity reactions being common along with nausea, vomiting, and diarrhea

Sulfonamides basic action

drugs that inhibit folic acid synthesis in bacteria

Sulfonamides adverse reactions

skin reactions, rash, stevens-Johnson sydrome, sunburn, photophobia’s, GI distress

Sulfonamides pertinent nursing information

-cross sensitivity allergies with thiazide diuretics

-have patient protect skin from sun ex.) hat, sunscreen, long sleeves

What are some examples of sulfonamides?

-cotrimoxazole

-sulfamethoxazole

-trimethoprim

Tetracyclines basic action

Inhibit protein synthesis in a wide range of bacteria, do not allow bacteria to multiply