Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
133 Cards in this Set
- Front
- Back
What phase of drug activity applies only to drugs that are administered through the gastro-intestinal tract?
|
Pharmaceutical Phase
|
|
What are 5 methods of administering drugs to the gastro-intestinal tract?
|
- by mouth
- naso-gastric, gastric, duodenal, or jejunal tubes |
|
During which phase of drug activity will drugs in solid form be disintegrated and dissolved by fluids in the stomach and small intestine?
|
Pharmaceutical Phase
|
|
Would you expect drugs in solid or liquid form to pass through the pharmaceutical phase quicker?
|
liquid
|
|
What phase of drug activity applies to all drugs and is characterized by movement of the drug?
|
Pharmacokinetic Phase
|
|
What is the first aspect of the pharmacokinetic phase? What is the second?
|
1. absorption
2. distribution |
|
(def)
the movement of a drug from its site of entry into the body to the blood stream |
absorption
|
|
(def)
the movement of the drug from the blood stream to the interstitial space of tissues and then into cells |
distribution
|
|
What phase of drug activity applies to all drugs and is characterized by bio-chemical actions of drugs and physiological responses to drugs?
|
Pharmacodynamic Phase
|
|
During which phase of drug activity do drugs modify existing functions of target tissue?
|
Pharmacodynamic Phase
|
|
Drugs can ________ or ________ cellular function of the body.
|
stimulate (agonists) or inhibit (antagonists)
|
|
Drugs given when endogenous substances such as thyroxine, insulin, or estrogen are diminished or absent is an example of _________ therapy.
|
replacement
|
|
Vitamins, minerals, or electrolytes are examples of _________ __________.
|
dietary supplementation
|
|
What is the 3rd aspect of the Pharmacokinetic Phase? What is the fourth?
|
3. metabolism
4. excretion |
|
(def)
a drug undergoes enzymatic transformation in the liver |
metabolism
|
|
(def)
during metabolism, a drug is transformed to a water-soluble form so it can be removed by the kidneys |
excretion
|
|
What are 3 variables that may affect the pharmaceutical phase?
|
- type of drug preparation
- ph of gastric fluid - incomplete swallowing |
|
Sustained-release preparations have ___________ that dissolve at variable rates.
|
coatings
|
|
__________ coated preparations are designed to resist disintegration in the acid environment of the stomach but will break down in the alkaline environment of the small intestine.
|
Enteric
|
|
Most oral drugs are disintegrated and dissolved more readily in fluid with ______ ____.
|
low pH (as found in the stomach)
|
|
(def)
the percentage of the drug dose that reaches systemic circulation |
bioavailability
|
|
What 3 things may affect bioavailability?
|
- route of administration
- degree of first-pass effect - degree of second-pass effect |
|
What are the routes used for drug administration? (14)
|
1. intravenous (parenteral)
2. intramuscular (parenteral) 3. subcutaneous (parenteral) 4. intrathecal (within the spinal canal) 5. intradermal (diagnostic testing such as PPD) 6. Oral 7. Sublingual 8. Buccal 9. Transdermal (patches placed on the skin) 10. Topical (rubbed into skin) 11. Rectal (suppositories) 12. Vaginal (suppositories, creams, troches) 13. Inhalation (inhalers, aerosols) 14. Instillation (eyes, ears, nose, vagina, rectum) |
|
What type of drug administration provides the greatest bioavailability? Why?
|
- Intravenous drugs because the drugs are delivered directly into the bloodstream
|
|
What type of drug administration has the least amount of bioavailability? Why?
|
Oral - due to the many factors that can affect the drug in the gastro-intestinal tract
|
|
"First-Pass effect" is also called what?
|
Hepatic First Pass
|
|
Does the first-pass effect increase or decrease bioavailability? Why?
|
Decreases - must pass from intestinal lumen to liver via the portal vein; the drug is partially inactivated by the liver before reaching systemic circulation
|
|
Does the second-pass effect decrease or increase bioavailability? Why?
|
increases- because the liver excreted unmetabolized drug into the bile and the gut reabsorbs the drug from the bile
|
|
What variables may affect absorption during the pharmacokinetic phase?
|
- Bioavailabiliy
- Route used for Drug administration - Degree of first pass - Degree of second pass - # of mucosal microvilli in the small intestine - gastric motility - presence or absence of food in the stomach - food-drug and drug-drug interactions |
|
Oral drugs mostly pass through the ________ ________ in the small intestine.
|
mucosal microvilli
|
|
What effect would malnutrition likely have on the absorption of oral drugs?
|
mucosal microvilli #'s are decreased due to malnutrition, hence absorption is reduced
|
|
Would there be an increase or decrease in absorption rate when a drug moves rapidly from the stomach to the small intestine? What about a drug that moves slowly from the stomach to the small intestine?
|
Fast moving drug = fast absorption
Slow moving drug = delayed absorption |
|
Milk reduces the absorption of _____ and ______.
|
iron and tetracycline
|
|
Orange juice enhances the absorption of ______.
|
iron
|
|
Grapefruit juice slows the metabolism of _______ ________ ______.
|
calcium channel blockers
|
|
Food rich in _______ and ______ decrease the absorption of many drugs.
|
calcium and iron
|
|
Products containing ________ decrease the absorption of most drugs.
|
aluminum (antacids)
|
|
What may occur when iron and levothyroxine (Synthyroid) are given together?
|
neither might be absorbed
|
|
What 4 factors may affect distribution of drugs during the Pharmacokinetic phase?
|
- circulation of blood
- degree of plasma protein binding - plasma protein levels - presence of tumors or abscesses |
|
How does poor circulation affect drug distribution?
|
it delays it
|
|
What are 2 examples of causes of poor circulation?
|
- shock
- vasoconstriction |
|
What structure in the blood is the site of attachment for drugs?
|
albumin
|
|
What is albumin?
|
a protein found in the blood
|
|
What type of drug activity would you expect to see in a drug that has a high degree of protein binding?
|
- slow onset of action with a longer duration
|
|
What type of drug activity would you expect to see in a drug that has a low degree of protein binding?
|
- rapid onset and a short duration
|
|
What problem may be encountered when a client is given 2 highly protein-bound drugs at the same time?
|
competition for protein binding sites which results in an increase in the amount of circulating free drug - could result in toxicity
|
|
Why is malnutrition such a problem in regards to the DISTRIBUTION of drugs?
|
because malnutrition can cause low levels of plasma proteins, thus reducing the # of binding sites - can result in toxicity
|
|
What problem do you think the presence of tumors or abscesses may cause for the DISTRIBUTION of drugs?
|
distribution is blocked
|
|
What are 2 variables that may affect Metabolism during the Pharmacokinetic Phase?
|
- Liver Disease
- The Length of the Half-Life |
|
Most drugs are metabolized by what?
|
the liver
|
|
What group of people often have a slower metabolism of drugs?
|
elderly
|
|
The longer the half-life, the longer it takes for what to occur?
|
the longer it takes for the liver to metabolize the drug
|
|
What are variable may affect the excretion of a drug during the Pharmacokinetic Phase?
|
- Renal Disease
|
|
Why are the elderly often slower at excreting drugs from the body?
|
- because they have a decrease in the # of functioning nephrons
|
|
During the Pharmacodynamic Phase, drugs exert bio-chemical effects in what 6 ways?
|
1. binding with cellular receptors
2. inhibiting the actions of enzyme or hormones 3. causing a chemical reaction 4. increasing osmolarity 5. combining with metals (chelating) 6. presence of their physical properties |
|
When binding with receptors, a drug has an affinity for receptors on cell surfaces. What makes this type of drug more or less effective?
|
the greater the fit between the drug and receptor, the more effective the drug
|
|
Drugs that inhibit the action of a specific enzyme do so how?
|
cause the enzyme to bind with the drug instead of target cells
|
|
What is an example of a drug that works via chemical reactions?
|
antacids - alkaline drug changes pH of acidic stomach
|
|
(def)
drugs that inhibit the action of a specific enzyme causing it to bind with the drug rather than the target cell |
antimetabolites
|
|
What drug can treat hypertension by binding with angiotensin? What type of drug type is this?
|
ACE inhibitors - these are examples of antimetabolites
|
|
Finasteride (Proscar) is an example of an antimetabolite. How does this drug work? What is it used to treat?
|
blocks the enzyme responsible for the formation of male hormones - used to treat prostate cancer
|
|
___________ disrupt the enzyme systems of bacteria and viruses that are responsible for the reproduction of their cells.
|
Antibacterials
|
|
What is an example of a drug that reduces swelling of the brain through osmosis?
|
Mannitol
|
|
How does Milk of Magnesia treat constipation?
|
pulls water into the colon via osmosis to loosen stool
|
|
__________ agents combine with toxin metals to form a complex that can be excreted in the urine.
|
Chelating
|
|
What are 2 examples of Chelating Agents?
|
1. Calcium EDTA
2. Penicillamine |
|
What is an example of a drug that exerts it action due to its physical properties?
|
Metamucil (for constipation)
|
|
When is polypharmacy most dangerous?
|
When clients are getting prescriptions from different doctors and especially when they are getting them filled at different pharmacies
|
|
True/False:
OTC drugs will never interact with prescription drugs. |
FALSE- although this is commonplace, it can be dangerous
|
|
A dose that is too small is ___________. A dose that is too large is _______.
|
too small = sub-therapeutic
too large = toxic |
|
What is the current theory on tolerance development?
|
the activation of excess drug-metabolizing enzymes and/or decreased sensitivity at the receptor sites
|
|
True/False
An individual who is tolerant to a drug may have a cross-tolerance to drugs in the same pharmacological family. |
True
|
|
A tolerance to morphine may cause a tolerance to what other drug?
|
codeine
|
|
The recommended dosage of a drug is targeted to a _____ pound person.
|
150
|
|
What two groups of people usually require smaller doses of drugs? Why?
|
Children and the Elderly because they metabolize drugs differently than adults.
|
|
True/False-
Men and Women respond to drugs differently. |
True
|
|
True/False-
Ethnicity and Race have no influence of drug responses. |
False- there can be differences among ethic and racial groups in their responses to drugs
|
|
True/False-
A person's knowledge of a drug and attitude toward taking the drug can influence the biological response. |
True
|
|
Some drugs have more effect while taken in the morning, others while taken in the evening. This is referred to as what?
|
diurnal response
|
|
(def)
The time it takes the drug to reach the minimum effective concentration in the plasma after it is administrated. |
Onset of Action
|
|
What phase begins at the onset of action?
|
Pharmacological action
|
|
(def)
the phase when the drug reaches the highest level of concentration in the plasma |
Peak Action
|
|
What phase it the drug most active?
|
Peak Action
|
|
(def)
the length of time a drug has a pharmacological effect |
duration of action
|
|
(def)
the ratio between the effective dose and the lethal dose |
Therapeutic index
|
|
Which is more dangerous? A drug with a narrow or wide therapeutic index?
|
narrow
|
|
(def)
the ratio between the minimum effective concentration and the minimum toxic concentration |
therapeutic range
|
|
What type of drugs would monitoring of therapeutic range be necessary?
|
those with a narrow therapeutic index
|
|
At what point should you draw blood to measure peak levels?
|
at the point when the drug "should" reach its peak
|
|
The peak level indicates the rate of _____________.
|
absorption
|
|
At what point should you draw blood to check the trough level?
|
right before the next scheduled dose is administered
|
|
The trough level indicates the rate of __________.
|
excretion
|
|
When are peak and trough levels usually drawn?
|
when certain intravenous antibiotics
|
|
(def)
the time it takes for one-half of the drug to be eliminated from the body |
biologic half-life (t 1/2)
|
|
(def)
a large initial dose that is given to quickly achieve a therapeutic blood level of a drug |
loading dose
|
|
The effect a drug has on the desired receptor is called what?
|
primary effect
|
|
(def)
the effect of a drug on the undesired receptor site is called what? |
side effect
|
|
The use of a drug for anything other than it's primary purpose is called what?
|
"off-label" or "unlabeled" use
|
|
(def)
a physiological response that is harmful to the body |
adverse reaction
|
|
(def)
an unexpected response from a drug |
idiosyncratic response
|
|
(def)
repeated doses of a drug accumulate in the body resulting in a greater than desired pharmacological effect |
cumulation
|
|
What are 3 examples of reservoirs where drugs might accumulate?
|
- bone
- adipose tissue - liver |
|
(Def)
2 or more drugs with similar actions are given simultaneously to increase the pharmacological effect |
summation (additive effect)
|
|
(def)
2 or more drugs with dissimilar actions are given simultaneously to create a pharmacological effect that is greater than the sum of the drugs when given independently |
Potentiation (synergism)
|
|
(Def)
an indication that a particular drug should not be given |
Contraindication
|
|
What type of iatrogenic effect?
nausea, vomiting, diarrhea, gastric mucosal irritation |
gastro-intestinal effects
|
|
What type of iatrogenic effect?
a decrease in the red and/or white blood cells (blood dyscrasias) |
Hematolgic effect
|
|
If a hematologic effect is suspected, what should be done?
|
Monitor CBC
|
|
What type of iatrogenic effect?
liver toxicity |
Hepatotoxicity
|
|
What type of iatrogenic effect?
kidney damage |
Monitor for increase in the blood urea nitrogen (BUN) and the serum creatinine.
|
|
What type of iatrogenic effect?
weight gain, hyperglycemia, fluid, and electrolyte imbalances |
Metabolic effects
|
|
What is an example of a drug group that may have metabolic effects?
|
steroids
|
|
What type of iatrogenic effect?
rashes, itching, changes in pigmentation |
dermatologic effect
|
|
What type of iatrogenic effect?
increased reaction of the skin to the sun |
Photosensitivity
|
|
What type of iatrogenic effect?
Sedation, agitation, psychosis |
Behavioral effects
|
|
What type of iatrogenic effect?
capable of causing cell mutation that may lead to cancer |
carcinogenic effects
|
|
What type of iatrogenic effect?
causes developmental disorders in the fetus |
teratogenic effects
|
|
What are the 5 pregnancy safety categories?
|
A
B C D X |
|
Which pregnancy category?
no evidence of risk to the human fetus |
A
|
|
Which pregnancy category?
Animal studies have not demonstrated a risk to the fetus; well-controlled studies in pregnant women are not available; assumed there is little to no risk |
B
|
|
Which pregnancy category?
Animal studies have shown an adverse effect on the fetus but there are no adequate studies in humans or there are no animal reproduction studies; drug may be given if the potential benefit to the mother outweighs the potential risk to the fetus |
C
|
|
Which pregnancy category?
There is evidence that there is risk to a human fetus; drug may be given if the potential benefit to the mother outweighs the potential risk to the fetus |
D
|
|
Which pregnancy category?
Animal and/or human studies demonstrate fetal abnormalities or adverse reactions; risk to fetus outweighs the potential benefits to the mother |
X
|
|
True/False:
Drugs do NOT pass into breast milk. |
False
|
|
What type of warning is issued by the FDA if a drug is known to cause a high incidence of iatrogenic effects?
|
Black box warning
|
|
Foreign substances stimulate what immunoglobulins?
|
IgE, IgG, or IgM
|
|
True/False:
A patient likely will not have an allergic reaction to a medication the first time they take it, although they could have a reaction in the future. |
True
|
|
What type of allergic reaction?
Occurs within minutes of exposure; characterized by pruritis, rash, urticaria and/or edema. Serious reactions can include apprehension, tachycardia, hypotension, bronchospasm, and respiratory tract edema. |
Type I
|
|
True/False:
Anaphylactic shock, as seen in Type I allergic reactions, can be fatal. |
True
|
|
What type of allergic reaction?
Characterized by an auto-immune response. Hemolytic anemia, thrombocytopenia or lupus erythematosus can be seen. Reaction is usually reversible weeks to months after drug is discontinued. |
Type II
|
|
What type of allergic reaction?
Characterized by fever, swollen lymph nodes, arthralgia, and enlarged spleen; usually occurs 1-3 weeks after exposure to the drug |
Type III
|
|
What type of allergic reaction?
Caused by sensitized T lymphocytes; results in contact dermatitis. Pruritis, rash, and urticaria usually occurs when touching the allergen. |
Type IV
|
|
What type of allergic reaction?
Many health care professionals have developed this type of allergic reaction to latex gloves. |
Type IV
|