Midterm - Combined deck Flashcards
What are the four basic pharmacokinetic processes? Hint: MOTIONAcronym: MADE
- absorption2. distribution3. metabolism4. excretion
MEtabolism + excretion = ___________
elimination
The movement of a drug from its site of administration into the blood?
absorption
Drug movement from the blood to the interstitial space of tissues and from there into cells (from blood to target)
distribution
AKA Biotransformation; enzymatically mediated alteration of drug structure.
Metabolism
Movement of drugs and their metabolites out of the body.
excretion.
What are the three ways a a drug can cross cell membranes?
- passage through channels or pores
- passage with aid of transport system
- direct penetration of the membrane itself.
In order to directly penetrate membranes, a drug must be ______ ______ .
Lipid Soluble (lipophilic) p.28Remember: Like dissolves like. If chemical is lipid soluble it can get through lipid membrane
The ____ of absorption is how soon effects will begin. The _____ of absorption helps determine how intense effects will be.
Rate;amount
Rate of dissolution, surface area, blood flow, lipid solubility and pH partitioning are all factors affecting _______.
absorption
The two common routes of drug administration are:
enteral and parenteral.
What is the difference between enteral and parenteral?
enteral is in the GI Tract. Parenteral is anywhere else. Usually means by IV,IM, SC.
Why does the site of drug administration matter? How does it change the effects?
The barriers to absorption associated with each route are different.
Does absorption take place when IV drugs are administered?
No. Absorption is the movement from site of administration INTO the blood. WIth IV, it goes directly into the blood.
What is the advantage to using IV for poorly soluble drugs?
The drugs can be dissolved in large volume of fluid and into the body through IV.
What is the recommended time for injecting a drug via IV? Why?
Over a 1 minute interval at least. It takes 15 second from arm to brain. We would have the chance to see any negative effects before emptying a syringe into the patient. p.33
What should you check for in IV solutions before administering drugs?
Check that drugs are in solution. If cloudy or contains particles, do not use!!!
What is the only barrier to absorption for IM administration?
the capillary wall; The same goes for SC (or SubQ)
What determines the absorption rate of IM administration?
- water solubility
2. blood flow at the site of injection.
If a drug is has poor solubility, even in IV solution, what method of administration can we use?
IM
What is a depot injection?
the administration of a sustained-action drug formulation that allows slow release and gradual absorption, so that the active agent can act for much longer periods than is possible with standard injections. Depot injections are usually given deep into a muscle.
What is a benefit to an IM Depot injection?
Long lasting means fewer injections
If your patient is on coumadin, warfarin or any other anticoagulant, can you give them IM medications?
No. The risk of bleeding is too high.
What are two barriers to absorption in the case of oral administration?
- GI Tract epithelial cells2. Capillary Wall
The rate and extent of drug absorption following oral admistration can be highly variable due to:1. solubility and stability of drug2. gastric and intenstinal pH3. gastric emptying time4. _____________________5. other drugs in system3. coatings on the drug itself
Food in the gut.
What is the safest administration?
oral! no risk of fluid overload, infection or embolism, reversible.
A ______ is a mixture of a drug plus binders and fillers, all of which have been compressed together.
tablet
An ________-________preparation is covered with material designed to dissolve in the intestine, but not the stomach. Those materials used in the covering include fatty acids, waces and shellac.
Enteric-Coated
________ - _________ preparations are capsules filled with tiny spheres which contain the actual drug. The spheres have their own coatings. Why?
Sustained-Release; because the coatings dissolve at different times, allowing the drug to be released over time.
Drug distribution (movement of drugs throughout the body via the blood) is determined by three major factors:
- blood flow to tissues
- ability of drug to exit vascular system
- ability to enter cells
Why are abscesses and tumors resistant to drug therapy?
no blood supply in abscesslimited blood supply in tumor
Drugs enter into the blood and are transported where to exit the vascular system?
Capillary beds
Only drugs that are _____ ______ or have a _______ _____ can cross the BBB.
lipid soluble ; transport system
what protein in the blood binds to free drugs in the bloodstream?
plasma albumin
T or F: Hepatic metabolism always results in the breakdown of drugs into smaller molecules.
False, sometimes is synthesizes a molecule larger than the parent drug.
Drugs must be converted from ______-soluble to _______-soluble so that they may be excreted from kidneys. The most important consequence of drug metabolism is promotion of renal drug excretion.
lipid;water
A drug that is pharmacologically inactive as administered, but becomes active in the body after conversion.
Prodrug (p.39)….like provirus…sits around and waits.
List some reasons children under 1 are at risk with medication…
- BBB not fully developed2. liver not fully developed3. Kidneys are not full developed.
_______ is the process of stimulating enzyme synthesis.
induction p.39
How can malnutrition effect hepatic-drug metabolism?
poor diet may be missing important cofactors required for the drug to metabolize/function.p.40
The most important organ for drug excretion is the ______.
kidney
What are the three steps in renal drug excretion?
http://www.youtube.com/watch?v=4X8pAizadWI
- glomerular filtration (moves drugs from blood to urine)
- passive tubular reabsorption (lipid soluble drugs move into blood)
- active tubular secretion (tubular pumps organic acid /base from blood to urine)
What are some examples of nonrenal routes of drug excretion?
- Breast milk
- Bile (bile goes to small intestine, then our through feces)
- Lungs (anesthetics)
- Sweat and Saliva (in small amts)
If we administer two drugs that use the same transport system, will excretion of them be delayed? if so, why?
Yes, because the renal tubules are like revolving doors and can only carry a limited number of drug molecules per unit of time.
T or F: There is a direct correlation between therapeutic and toxic responses and the amount of drug present in plasma.
True. We can measure concentration in plasma instead of at the site (ie. can’t take sample from epileptic brain). p.43
Two plasma drug levels are super important:
- minimum effective concentration;
- ______ ______
toxic concentration
T or F: Concentration of drug must be at or above MEC.
TRUE; MEC = MINIMUM!
The _______ range is between the MEC and the toxic concentration.
Therapeutic Range
Which drug is harder to administer, one with a broad or narrow therapeutic range?
narrow. broad has more room to move within the range.
____ ___-___ is defined as the time required for the amount of drug in the body to decrease by 50%. Affects the potency for a medication.
Drug Half-Life
T or F: Regardless of the size of the dose, reaching the plateau takes the same amount of time for that particular drug.
True. The grams in the body would be greater, but the time it takes would not be different since it is always based on half-life (the time it takes to leave the body).
Fluctuations are seen between doses. The high concentration is called peak. The low concentration is the trough. How can we reduce fluctuations in drug levels?
- Administer by continuous infusion
- Administer depot preparation
- reduce the size of each dose and the dosing interval simultaneously.
The longer the half-life, the longer it takes to plateau. What can be done to reach the initial high level quicker upfront?
Administer a loading dose. By definition it is a large initial dose. p. 45
After the loading dose, _______ doses are given.
maintenance
T or F: It takes four half-lives for a drug to clear the body.
True. Each drug has it’s own individual half-life (length of time). It will take four of those to clear the system.
Avoirdupois 1kg = ___ lbs?
2.2 lbs
Gr stands for?
grain
dr stands for ?
dram
how many minims is 1 dram?
60 minims (60 minute drama on tv)
oz means?
ounce
how many ounces in a cup?
8 oz
how many cups in a pint?
2 cups
what does the symbol “T” stand for? How about “t”?
T = Tbspt= tsp
how many mL is 1 t?
5 ml
how many mL is 1T?
15 ml
how many pints to 1 quart?
2 pints
How many micrograms (mcg) to 1 gram?
1 million (1,000,000) mcg
how many grams to 1 kg?
1000g
The study of drugs in humans
Clinical Pharmocology
Use of drugs to diagnose, prevent, or treat disease or to prevent pregnancy. Also considered medical use of drugs.
Therapeutics (aka pharmacotherapeutics)
Any chemical that can affect the living processes.
Drug
Study of drugs and their interactions with living systems.
Pharmacology
What are the three most important characteristics that any drug should have?
Effectiveness (most important), Safety and selectivity.
Is there such thing as a safe drug?
No. All drugs have the ability to cause injury, esp with high dose and/or prolonged use.
How can we reduce the chance of adverse effects?
Proper drug selection and proper dosing.
What does selectivity mean?
A drug that elicits only the response it was given for.
T or F: We want drugs to be reversible and predictable.
True.
What is the therapeutic objective?
To provide maximum benefit with minimum harm.
What factors determine the intensity of drug responses.
- Administration (dosage, time, route)2. Pharmacokinetics3. Pharmacodynamics
(In human body) Drug absorption, distribution, metabolism and excretion are four major ______ processes.
Pharmacokinetics
Impact of the drug on the body once it reaches its target site?
Pharmacodynamics
The _____ - ____ _____ refers to the rapid hepatic inactivation of certain oral drugs (liver metabolizes quickly). When the drug is absorbed from the GI tract, they are carried straight to the liver. If the capacity of the liver to metabolize the drug is high, the drug becomes completely inactivated with no therapeutic effect.
First Pass Effect
For a great short video:
http://www.youtube.com/watch?v=QVCNfja7wkk
http://www.youtube.com/watch?v=xiuWdJYyIKs
What can we do to circumvent (bypass) the first-pass effect?
administer the medication parenterally (under the tongue, through injection or IV). This allows it to reach therapeutic levels in the systemic blood and bypass the liver. Gets to the site of action before hitting the liver.
The study of the biochemical and physiologic effects of drugs and the molecular mechanisms by which those effects are produced.
Simply put, the study of what drugs do to the body and how they do it?
Pharmacodynamics
____-_____ ______ is the relationship between the size of an administered dose and the intensity of the response produced.
dose-response relationship
Is the dose-response relationship graded or all-or-nothing? what is the importance of this?
Graded, which gives us more control and allows us to fit the needs of the patient. If it were all-or-nothing, and could only produce one intensity of response, we could not treat various patients with that drug.
_____ _____ is defined as the largest effect that a drug can produce. It is indicated by the height of the dose-response curve.
Maximum Efficacy
T or F: A drug with very high maximal efficacy is more desirable than a drug with lower efficacy.
False, we want to match the intensity of the response to the patient’s needs. Ex. Furosemide can cause dehydration because it is a high efficacy diuretic. We may choose a lower efficacy to reduce the intensity of volume of water to be mobilized.
The term ______ refers to the amount of drug we must give to elicit an effect.
potency
If morphine produces pain relief at a lower dose than meperidine, is it more potent or less potent?
more potent
Drugs are chemicals that interact with chemicals inside the body. ________ are the special chemicals in the body that produce effects. It is any functional macromolecule in a cell to which a drug binds to to produce effects.
Receptors
The binding of drugs to receptors can either _____ or ____ the action of the body’s own regulatory molecules.
mimic (agonist) or block (antagonist)
T or F: Drugs produce their therapeutic effects by helping the body use its pre-existing capabilities. Drugs cannot give cells new functions.
TRUE
There are four primary receptor families.
- Cell membrane embedded ______
- __ protein-coupled systems
- ligand-gated ____ channels
- transcription factors
- enzymes
- G
- ion
Transcription factors differ from other receptors in two ways. 1. They are found _____ the cell rather than _____ the cell. 2. Responses to activation of these receptors are _____ instead of _____.
p.52
- inside/within the cell rather than outside the membrane
- delayed versus instant, or within milliseconds.
Transcription factors are situated in the nucleus on the DNA; therefore, they can only be activated by ______ that are ______ soluble.
ligands; lipid
The more selective a drug is, the fewer side effects it will produce. Why is that?
Selective drug action is possible because drugs act through specific receptors. p.52
If drugs are selective for one receptor only, why does the drug still cause some side effects?
The receptor may be located in more than one area of the body, causing side effects.
_______ _______ Theory states that the intensity of response to a drug is proportional to the number of receptors occupied.
Simple Occupancy Theory
The strength of the attraction between a drug and its receptor.
Affinity
T or F: Drugs with high affinity (attraction to receptors) can bind when present in low concentrations. This means drugs with high affinity are potent.
True.
This term refers to the ability of a drug to activate a receptor upon binding. The higher this activity, the more intensely a receptor is activated.
intrinsic activity
Affinity is to potency as Intrinsic activity is to ______ _____. Drugs with high intrinsic activity cause intense receptor activation, therefore intense responses.
maximal efficacy
T or F: Agonists are molecules that activate receptors. These molecules include neurotransmitters, hormones, other endogenous regulators as well as drugs that mimic them.
TRUE
__________ produce their effects by preventing receptor activation by endogenous regulatory molecules and drugs.
antagonists
Affinity allows the agonist to bind to receptors. What does intrinsic activity allow?
Allows the bound agonist to activate or turn on the receptor function. p.54
T or F: If there is no agonist present, antagonist will still have an effect.
False. antagonist prevents agonist from activating receptor. If there is no activation, antagonist cannot deactivate.
Antagonist can be competitive or non-competitive. Non-competitive bind ________ to receptors. They reduce the maximal response an agonist can elicit.
irreversibly.
Because irreversible they are rarely used therapeutically.
Because competitive antagonists bind reversibly to receptors, the inhibition they cause is _________.
surmountable.
What causes down-regulation? Hint: Down-regulation is also referred to as desensitized or refractory.
When receptors of a cell are continually exposed to an agonist, the cell usually becomes less responsive.
Does-response curves demonstrate efficacy and potency. There are three phases:
Phase 1 - does is too low to elicit a response (curve relatively flat)
Phase 2 - bigger dose elicits a bigger response (curve climbs upward)
Phase 3 - ______________ (curve levels off)
Phase 3 - bigger doses are unable to elicit a further increase in response.
What are the seven rights of medication administration?
Right Patient, Drug, Dose, Time, Route, Technique, Documentation.PRTTDDD
How can you ensure you have the right patient?
Ask the patient for his or her name and birthdate. Double check ID bracelet.
How can you double check that you have the correct drug?
CHECK LABEL!!!!
- Check before taking from shelf.
- Check before pouring the drug out.
- Check before putting bottle back on shelf.
If you suspect that a doctor prescribe an incorrect dose, what do you do?
Double check before administering.
Does the condition of the liver matter in dosing?
Yes, if the liver does not function properly, a toxic amount of medication could build up.
T or F: Drug administration takes place in the hospital at times the patient chooses?
False. Drugs such as antibiotics have regular intervals at which drugs must be given to be effective.
Can you rely on the pharmacy to send the correct form of a medication or must you alert them as to your patient needs.
We must alert. Where the medication will be given depends on the patient and his/her condition. If they cannot swallow, we may need an IV or GI version.
If you are unsure of where or how to administer a medication, what can you do?
Access written procedure manuals available in the workplace.
When you are documenting (charting), what info must be included about drugs you administered?
Drug,Dose,Route, lot#, expiration date.
What are some important physical factors to consider before administering drugs?
Age, weight, nutrition, gender, culture, environment, pregnancy and organ function.
Where can I find a list of commonly confused drug names?
http://www.ismp.org/tools/confuseddrugnames.pdf
What do abbreviations tell us? examples: ID, qid, IM
When a med may be taken, how often it can be take, where it should be administered.
The sinister hand is the left, with which many countries use for “dirty” deeds such as toileting. Remeber S is for left. So what is D?
Dextrous - Right
If someone writes a.s., what location on the body are they referring to?
Hint: The letter “a” looks like an ear.
a = ear s = sinister left
Left Ear
The abbreviation “U” means what?
“Both”Remeber: U for union…
What does “bid” abbreviation mean?
bid = bi daily = twice daily
What does the abbreviation o.d. mean?
right eyeRemeber: “o” looks like an eye
NPO?
nothing per oral
IV
intravenously
IM
intramuscularly
ID
intradermallyDef:1. within the dermis.2. intracutaneous.
What does the abbreviation of “C” w /line over the top of it mean?
with (c with a line)
qid?
4x a dayquattro times a day (cuatro - espanol)
s with a line
without
SC
subcutaneously (into fat)
tid
three times perday
If a diabetic patient is NPO, should you administer insulin?
no, there is no food to interact with.
Where can I find a sample med schedule for patients to use at home?
page 30 - watkins
Why is nutrition an important factor when administering medication?
Some nutrients may be needed for absorption of med. Some nutrients may block absorption.
Although there are normal doses for some medications, may that does change if the patient is an amputee or obese?
Yes.
How does age effect medication administration?
Geriatric patients (over 55) may have decreased muscle mass and function of organs. Examples: Liver - decrease in metabolism / Kidney - decrease in filtration
What is polypharmacy? What is the issue with polypharmacy?
Taking several meds for more than one problem; it increases risk of side effects and interactions.
What do you need to do if you think a child may be having an adverse reaction to a medication you administered?
Fill out a MedWatch form.
Why does gender matter in drug administration?
Men have more muscle to fat compared to women. Medication is absorbed and distributed more quickly in men.
A ________ drug causes deformities when it crosses the placenta.
Teratogenic
Which organs are most affected by SYSTEMIC drug accumulation?
Kidneys, liver, heart
Liver produces ____ ______. A decrease in these levels, can alter the capacity of a drug to bond.
serum protein
Why is it important to educate patients in their own language?
Misunderstanding can lead to injury, overdose, or subtherapeutic treatment (not producing a therapeutic effect).You must tell them the risks of taking too much.
Patients can refuse medication. What can you do to help them feel better about taking it? (patient consent p.35)
Educate them on what it is for, how to take it, etc. If they still refuse, let them know risks of not taking the treatment. Do not force them . Technically forcing med on someone is considered assault and battery. It is there choice. Inform the dr and chart that they refused treatment.
What does HIPAA stand for?
Health Insurance Portability and Accountability Act
______ allows patient control over their medical record include access and how it is shared with other.
HIPAA
If, after being notified that your patient has ingested a toxic substance, you activated the emergency response system and were connected to poison control, what may you be asked to do? (Hint: Steps to treating the patient)
- Administer charcoal (binds with poison); usually after stomach pumping (lavage)
- Have patient drink large amount of water to dilute poison
- Have patient drink milk to reduce acidity.
- Monitor patient for symptoms: HR, Resp Rate, Seizures, etc.)
What is the name of the syrup that induces vomiting? Why is it no longer suggested?
Ipecac. Not effective and can cause complications.
Before administering medication (including emergencies), what should you ask the patient?
Are you allergic to any medications?
Why is important to observe a patient for 15 minutes following an injection antibiotic or allergy shot?
To watch for allergic reaction. Document this in your charts!
If a patient has swelling in the neck, difficulty breathing, itching, wheezing, anxiety and light-headedness, they may experiencing __________.
Anaphylaxis - a sever allergic reaction
T or F: Some drug interactions are desired.
True.
When drugs interact, there are three possible outcomes. List them.
- One drug may intensify the effects of the other
- one drug may reduce the effects of the other
- the combo can produce a new response not seen with each drug individually.
What is the term used for the type of interaction where one drug intensifies the other?
potentiative (poh ten she uh tiv)
Drug interactions can occurs when combined in an IV solution. They may form a precipitate. What should you do if a precipitate forms? Should you rely on a precipitate to form to know whether or not an interaction has taken place?
If you see a precipitate in an IV, the IV must be discarded.You cannot rely on the precipitate because it does not ALWAYS happen. You must NEVER combine two drugs in one IV unless it has been established that a direct interaction will not occur.
if the pH increases does it become more basic or acidic?
Basic
if a drug were to increase extracellular pH, would it increase the ionization of a acidic drugs?
Yes.
How do drugs increase the metabolies?
by inducing synthesis of hepatic drug metabolizing enzymes..
How does a drug causing reduction in cardiac output decrease drug filtration?
Glomerular filtration is decreased by drugs that decrease cardiac output. The blood flow is reduced, decreasing excretion.
What are a some simple things we can do to minimize drug-drug interactions?
- Take a thorough drug history
- Encourage patients to share any “street drugs,” supplements and OTC drugs they are taking.
- Monitor for early signs of toxicity.
How does grapefruit juice raise drug levels in the blood?
By inhibiting metabolism. The drug becomes built up in the system.