Exam I Flashcards
A pathological barrier leading to individual drug variations include:
A. Age
B. Kidney function
C. Family history
B. Kidney function
The concentration of the drug at the receptor is primarily determined by:
A. pharmacokinetics
B. pharmacodynamics
C. administration
B. pharmacodynamics
The best clinical evidence for drug effectiveness comes from a:
A. large, random-controlled trial with double-blinding
B. large, random-controlled trial with single-blinding
C. small, random-controlled trial with double-blinding
D. small, random-controlled trial with single-blinding
A. large, random-controlled trial with double-blinding
Off-label use refers to using a drug:
A. which is a generic substitute for the ordered trade drug.
B. which is a close-substitute for the ordered trade drug.
C. for a purpose approved by the FDA.
D. for a purpose not approved by the FDA
D. for a purpose not approved by the FDA
Most adverse drug effects are identified in phase \_\_\_ of clinical testing. I II III IV
Phase III
The preferred drug name to eliminate confusion among health care providers is the: A. chemical name B. trade name C. generic name D. common name
C. generic name
Contraindication
A pre-existing condition that prevents use of a drug under all but the most severe circumstances
Precaution
A pre-existing condition that significantly increases the likelihood of an adverse reaction
Not life threatening
Adverse Drug Reactions (ADR)
Noxious, unintended, and undesired effect that occurs at normal drug doses.
Mild: Drowsiness, nausea, itching, rash
Severe:
Respiratory depression, neutropenia, liver injury, anaphylaxis, hemorrhage
Risk Factors for ADRs
Elderly or very young
Severe illness
Multiple drug use
Side effects
Nearly unavoidable secondary drug effect produced at therapeutic doses.
Generally predictable
Develop immediately, or weeks to months
Intensity usually dose-dependent
Examples
Aspirin- gastric irritation
Antihistamines- drowsiness
Toxicity
Detrimental physiological effects caused by excessive dosing.
Examples
Morphine- respiratory depression
Insulin- severe hypoglycemia
Sometimes used to indicate a severe ADR
Ex. Neutropenia by anticancer drugs
Idiosyncratic Effect
Uncommon drug response resulting from a genetic predisposition.
G6PD deficiency (African and Mediterranean descent - Aspirin causes red blood cell hemolysis
Slower inactivation of a drug, allowing effects to last longer
- Ex. Succinylcholine (Muscle relaxant) – malignant hyperthermia
Paradoxical Effect
Effect opposite of intended drug response
For example, a sedative may cause nervousness or agitation.
Iatrogenic Disease
A disease produced by a healthcare provider or by a drug.
Ex. Some antipsychotic drugs may cause symptoms similar to Parkinson’s disease.
iatros- physician
-genic to produce
Carcinogenic Effect
The ability of certain medications and environmental chemicals to cause cancer.
Hepatotoxicity
Drugs are the leading cause of liver failure
Metabolism produces toxic metabolites
Drug combinations increase the risk of liver damage – alcohol & Tylenol
Monitor liver function tests (LFTs)
Signs and Symptoms of Liver Damage
Jaundice, dark urine, light-colored stools, nausea and vomiting, malaise, abdominal discomfort, loss of appetite
QT Interval Drugs
Prolong QT interval on ECG Increased ventricular repolarization time Risk of ventricular dysrhythmias Caution using in patients with: Dysrhythmias Elderly Low potassium or magnesium Women (longer QT intervals than men)
Nephrotoxicity
kidney damage
Monitor blood urea nitrogen (BUN), creatinine, creatinine clearance, urinalysis
Bone Marrow Toxicity
bone marrow damage
Monitor periodic blood counts
Ototoxicity
inner ear damage
MEDWATCH
MEDWATCH is the FDA Medical Products Reporting Program.
You can file your report electronically via their internet site (www.fda.gov/medwatch).
This is an important program for bringing ADRs and product problems to light.
An unwanted reaction caused by an overdose is: A. an adverse drug reaction. B. a side effect. C. a toxicity. D. an allergic reaction.
C. a toxicity
Anaphylaxis is defined as all of the following except: A. bronchospasm. B. laryngeal edema. C. hypotension. D. rash.
D. rash
An idiosyncratic effect is defined as:
A. an immune response triggered by prior exposure.
B. an uncommon response resulting from a genetic predisposition.
C. a disease caused by a provider or drug.
D. the ability to cause cancer.
B. an uncommon response resulting from a genetic predisposition
Medication Guides
Medication Guides
FDA approved guides to educate patients about how to minimize harm from dangerous drugs
MedGuides are required:
Patient adherence to directions is essential
Potential for serious side effects is present
Black Box Warnings
Black Box Warnings
Strongest safety warning a drug can carry and still be on the market
Required for drugs with serious or life-threatening risks
Identify the highest-risk patient for adverse drug effects: A. 25-year-old male with a leg fracture B. 70-year-old male with alcoholism C. 5-year-old female with Strep. throat D. 15-year-old with appendicitis
B. 70-year-old male with alcoholism
Safe Medication Administration –
6 Rights
Client/Patient Drug Dose Route Time Documentation
Mnemonic: Patients Do Drugs Round The Day
What is the blood-brain barrier? Name two ways drugs enter the brain.
The capillaries of the brain do not have gaps between the cells of the capillaries. Drugs must pass through the cell membrane or be transported by a transport system.
The cytochrome P450 system refers to a family of enzymes which does what?
Metabolize drugs.
Kidneys are unable to excrete what type of drugs?
Highly lipid-soluble.
Define prodrug.
An inactive compound which can be converted into an active drug.
Define the first-pass effect.
Blood passes through the liver before reaching the systemic circulation.
How do hepatic inducers affect the rate of drug metabolism?
Increases.
If a drug binds to albumin and displaces another drug from the site, what happens to the serum concentration of the drug displaced?
Increases
At what age does the infant’s liver develop into its full capacity?
One year.
The most important organ for drug excretion is what?
The kidneys.
Which drugs remain in the urine for excretion?
Polar and ionized drugs.
Define enterohepatic circulation.
Drugs excreted in the bile are reabsorbed into the portal blood.
What type of drugs easily enters breast milk?
Lipid-soluble or lipophilic
Define the minimum effective concentration (MEC).
The plasma drug level at which a drug has a therapeutic effect.
Define toxic concentration.
The plasma drug level at which toxic effects begin.
Define therapeutic range.
The range of plasma drug levels that fall between the MEC and the toxic concentration.
Define duration.
The length of time the drug is in the therapeutic range.
Define half-life.
The time required for the amount of drug in the body to decrease by 50%. For example if the half-life is one day, in 1 day, 50% is left; in 2 days, 25% is left; in 3 days, 12.5% is left; etc.
How many half-lives does it take to clear a drug from the body? What about the half lives of metabolites?
4 half-lives.
Some metabolites may have longer half-lives than the drug itself.
Define plateau. What is the relationship between absorption and elimination?
Steady concentration of drug reached after repeated doses.
Absorption = Elimination
Why are loading doses given?
To shorten the time to plateau.
Why are maintenance doses given?
To continue the plateau.
What type of drugs cross the placenta?
Lipid-soluble or lipophilic.
Define pharmacokinetics.
The study of drug movement throughout the body.
The cell membrane is composed of what?
A double layer of molecules known as phospholipids.
Name two ions which can pass through channels or pores.
Na+ and K+
Define transport system. Is it selective or nonselective?
A system which transports drugs from one side of a cell membrane to another.
Only carries drugs with a particular structure.
What type of drug can penetrate a cell membrane?
Lipophilic or lipid-soluble
List two types of non-lipid soluble drugs.
Polar molecules and most ions
Define polar molecule. They dissolve well in what solvent?
Molecules which have an unequal or uneven distribution of electrons yet no net charge.
Water.
Define ion.
Atoms which have a net electrical charge.
An acid tends to ionize in what type of environment?
Base
A base tends to ionize in what type of environment?
Acid
Explain ion trapping or pH partitioning.
When there is a pH gradient between two sides of a cell membrane, acidic drugs will ionize and stay on the basic side. Basic drugs will ionize and stay on the acidic side. Ionized drugs do not cross cell membranes.
Define absorption.
The movement of drug from its site of administration into the blood.
Rapidly dissolving drugs will have what type of onset?
Rapid
An increased surface area for absorption will cause absorption to increase or decrease?
Increase
Drugs are absorbed more rapidly in areas where blood flow is what?
High
What types of drugs are absorbed rapidly through the cell membrane?
Lipophilic or lipid soluble
Delayed gastric emptying may delay the absorption of a drug meant to be absorbed where?
Intenstines
Parenteral drugs refer to routes of administration where?
Outside the GI tract.
What is the rate of absorption for intravenous administration?
Instantaneous.
What is the barrier to intramuscular absorption?
Capillary wall.
What types of drugs are absorbed from intramuscular and subcutaneous sites?
Poorly soluble drugs (water-soluble)
Which route is the safest for drug administration?
Oral
Define chemically equivalent.
Drugs contain the same amount of the identical chemical compound.
Define bioavailability.
Drugs contain the same amount of the identical chemical compound and are absorbed at the same rate and to the same extent.
Where are enteric-coated drugs meant to dissolve?
Intestine
Why are sustained-release capsules utilized?
Maintain a steady release of the drug all day.
What is the most common mechanism by which drugs enter a cell?
Direct penetration of the membrane
Should enteric-coated drugs be crushed? Why or why not?
No, the drug would interact with stomach acids.
What does the p-glycoprotein do?
It is a transmembrane protein which transports drugs out of the cells back into the blood stream or into lumens such as renal tubules or intestinal lumens.
What is a quaternary ammonium compound?
It is a compound with at least one nitrogen atom which has four bonds rather than three bonds. It has a positive charge and is unable to cross most membranes.
How long should a drug be administered intravenously to ensure the lowest serum concentration of the drug in the circulation?
Over one minute to fully distribute drug within entire blood volume.
List three most important properties of drugs. Which is the most important?
Effectiveness, safety, selectivity.
Effectiveness most important.
What does selectivity mean?
Produces only desired responses for which it is given.
List three types of drug names. Which is the best for communicating between health professionals?
Chemical, generic, trade
Generic name is the best.
What factor primarily determines the drug concentration at the receptor?
Administration.
Pharmacokinetics determines what?
How much of a drug reaches the sites of action
List four processes of pharmacokinetics.
Absorption, distribution, metabolism, excretion
How does changing the route from intravenous to oral influence dosage?
Oral dosages are usually higher than intravenous dosages, because there is a barrier to absorption.