Pharmacology Lecture Flashcards
What are PT responsibilities related to Medication Management?
Monitor and report
- desired effects
- Adverse effects
- toxic effects
- Vital signs during treatment
What should we coordinate Pt treatment with in terms of medications?
optimal drug effects
What do we need to schedule PT around to maximize the drug’s effects?
The drug schedule
What do PTs need to be able to recognize in terms of medications?
Drug-related side effects and adverse reactions
What should PT’s be knowledgeable on in terms of drugs the patient is taking?
Potential drug interactions
What do PTs have to monitor while doing activity and exercise in terms of drugs?
Responses to medications
What does patient and family education and compliance result in?
safe administration of drugs
adherence to a medication schedule
appropriate doses and frequence
What do we encourage the patient and the family to do in terms of pharmacies?
Encourage centralization of medication through use of one pharmacy
What is the chemical in terms of drug nomenclature?
specific structure of the compound
What does generic mean in terms of drug nomenclature?
non-proprietary name, used in US pharmacopeia
What is a trade name in terms of drug nomenclature?
Assigned by pharmaceutical companies, copyright name
How long does it take to get proprietary rights through a patent?
20 years
How long does drug discovery take?
2-5 years
How long does pre-clinical development last?
1.5 years
How long does Clinical development last?
5-7 years
How long does it take to get regulatory approval?
1-2 years
What is phase IV?
Postmarketing surveillance
When does drug exclusivity mean?
a period of time when a brand-name drug is protected from generic drug competition.
What does drug exclusivity promote?
A balance between drug innovation and generic drug competition
When does drug exclusivity begin?
Upon drug approval
Some drugs have both ________ & __________ protection
Patent
Exclusivity
How long do new brand-name drugs have exclusivity?
5 years
How long is orphan drug exclusivity?
7 years
What is an orphan drug?
a brand name drug for a disease or condition that effects fewer than 200,000 people in the US
What is new clinical investigation exclusivity?
A brand name drug with an active ingredient that has been approved before, but being administered in a new way
How long does clinical investigation exclusivity last?
3 years
What organization controls drug regulation?
FDA
Food and Drug Administration
What are the purposes of drug regulation?
-balance needs of the drug companies and the patient
- ensure safety and efficacy of drugs
- regulate manufacturing process
- control public access to drugs with the potential for abuse
What does the drug enforcement administration do?
Classifies drugs into 5 categories(schedules) based on their acceptable medical use and potential for abuse or dependency
What do schedule 1 of drugs contain?
High dependance, high abuse potential
What are examples of schedule 1 drugs?
heroin, LSD, Cannabis
What do schedule II drugs contain?
medical use, high potential of dependance, high abuse potential
What are examples of schedule II drugs?
Vicodin, cocaine, Dalaudid, Demerol, OxyContin
What do schedule III drugs contain?
Medical use, mod to low potential for dependance, mod to low abuse potential
What are examples of schedule III drugs?
Tylenol w/ codine, testosterone, anabolic steroids
What are some characteristics of schedule IV drugs?
Medical use, low potential for dependance, low abuse potential
What are some examples of schedule IV drugies?
Xanax, Soma, Ambien, Darvon
What are some characteristics of schedule V drugs?
medical use, low potential for dependance, low abuse potential
What are some examples of schedule V drugs?
Cough, antidiarrheal drugs
What are characteristics of an ideal drug?
Effectiveness, safety, selectivity, reversible action, predictability, freedom from drug interactions, low cost, chemically stable, simple generic name
What is a pharmakon?
Drug, medicine, or poison
What is logia?
Study
What is the definition of pharmacology?
The unified study of the properties of chemicals and living organisms and all aspects of their interaction
Pharmacology can be split into what two fields?
Pharmacotherpeutics and toxicology
What can pharmacotherapeutics be split into?
Pharmacokinetics and pharmacodynamics
What are pharmacokinetics?
Drug absorption, distribution, metabolism, excretion
What are pharmacodynamics?
Cellular and systemic effects
What is a desired dose?
large enough dose to reach the target site and produce a beneficial response but small enough to prevent / minimize unwanted side effects
What are dose response curves used for?
Provide info about the dosage range over which the drug is effective
What does the quantal dose response curve show?
Shows the percentage of people who show the desired response
What does a ED 50 dose response curve show?
The percentage of people who show the desired response at 50% of the dose
What can we have as a part of the quantal dose response curve?
Analgesia
Nausea
Respiratory depression
What is the therapeutic index?
TD 50 over ED 50
What is the margin of safety?
TD 0.1 / ED 99.9
What does the graded dose response curve graph do instead of the others?
Instead of graphing % of people responding, graphs % of maximum response
What does the graded dose response curve allow us to compare?
Efficacy and potency of different drugs
What is efficacy?
degree to which a drug is able to induce maximal effects
What is potency?
The amount of drug necessary for obtaining the desired effect
What is a drug mechanism of action?
The means by which the presence of a drug produces and alteration in function
Drugs usually must combine with a ___________ ________________ to produce an effect
Cellular receptor
What happens following a receptor binding during the drug’s mechanism of action?
An ion channel is opened/ closed
2nd messengers are activated
normal cell function is inhibited
normal cell function is activated
Why are selective drugs better than nonselective drugs?
they are more beneficial and have less side effects than non selective drugs
What is an agonist in terms of a drug?
encourage cell function
What does an antagonist do in terms of drugs?
Blocks cell function
What is an antaonism?
Drug inhibits the effect of another drug
What is an altered absoption?
Drugs may inhibit absorption of other drugs across biologic membranes
What is an altered metabolism?
Induction or competition for metabolizing enzymes
What is plasma protein competition?
Drugs that bind to plasma proteins may compete with other drugs for protein binding sites.
What is addition in terms of drug interactions?
The response elicited by combined drugs is EQUAL to the combined responses of the individual drugs
What is synergism in terms of drug interactions?
The response elicited by combined drugs is GREATER THAN the combined responses of the individual drugs
What is potentiation in terms of drug interactions?
A drug which has no effect enhances the effect of a second drug
What is antagonism in terms of drug interactions?
A drug which inhibits the effect of another drug
What are ways that a patient can vary?
Body weight and size
age
genetic factors
pregnancy status
smoking and drinking habits
liver or kidney disease
drug tolerance
What does the body do with the drug?
Administration
absorption
distribution
elimination
What is an enteral route of drug administration?
Through the alimentary canal
What is a parenteral route of drug administration?
Around the GI tract
How do we take enteral drugs?
oral
sublingual
rectal
How do we take parenteral drugs?
Intramuscular
subcutaneous
Intravenous
Intradermal
Local
(INJECTIONS)
How do we take topical drugs?
Epidermic
instillation
irrigation
How do we take drugs that are inhaled?
Vapotization
Gas inhalation
Nebulization
What does first pass effect dimish?
Bioavailability of a drug administered orally
How do drugs travel through the GI system?
Swallowed drugs -> digestive system -> hepatic portal system -> liver -> rest of body
What is an advantage of oral drugs?
Indep administered
convenient
economical
What is a disadvantage of oral drugs?
Must be conscious and aware, first pass effects
What is an advantage of sublingual drugs?
Indep administered
convenient
Avoids first-pass effects
What is a disadvantage of sublingual drugs?
More expensive
May be inconvenient
What is an advantage of rectal drugs?
By-passes liver
Good for older and younger
Unconscious patients
slow, steady effect
What is a disadvantage of rectal drugs?
Unpredictable absorption
uncomfortable
What are examples of parenteral routes of administration?
Intravenous
Intramuscular
Subcutaneous
Inhalation
Topical
Transdermal
What is absorption of drugs do?
Transfers the drug to the blood stream
What can affect absorption of the drug?
Molecular size and shape
solubility at the site
degree of ionization
lipid solubility
What are patient associated factors affecting absorption?
Route of administration
blood flow
tissue permeability
binding to plasma proteins
disease process
storage
What is distribution of a drug?
Transfer of drug from the blood stream to specific organs/ compartments
What are the distribution concepts?
Transport mechanisms
Volume of Distribution
Bioavailability
What are transport mechanisms?
- passive diffusion
- active transport
- facilitated diffusion
- endocytosis
Which transport mechanism is most important for drug transport?
Passive diffusions
What does passive diffusion depend on?
Concentration gradient
lipid solubility
channels/pores
Passive diffusion moves from _____ concentration to _____ concentration?
High to low
Is there energy expenditure with passive diffusion?
NO
What is active transport?
Carrier specificity
Does active transport require expenditure of energy?
YES
Where does active transport move substances?
Against a concentration gradient
Low to high
What is facilitated diffusion?
Uses a carrier protein to assist transport
Does facilitated diffusion use energy?
No energy expenditure
Where does facilitated diffusion move contents?
With the concentration gradient
high concentration to low concentration
What is endocytosis?
A drug is engulfed via invagination of cell membrane
Does endocytosis require energy expediture?
NO
Where does endocytosis move contents?
With a concentration gradient
High concentration to low concentration
What is volume of distribution?
the amount of the drug that actually reaches the target site
What is the volume of distribution?
The ration of the amount of drug administered to the concentration of drug in the plasma
How many liters is the total body fluid?
42 L
What is the plasma volume of distribution?
3L
Extracellular volume of distribution?
16L
Volume of distribution involves the volume of the drug in …
Plasma
Intracellular water
adipose tissue
interstitial water
organs
If there is more of the drug in the plasma, there is a _____ volume of distribution
low
If there is less of the drug in the plasma, there is a ______ volume of ditribution
high
What does bioavailability depend on?
Route of administration
first-pass effects
drug’s ability to cross membrane barriers
What kind of drugs are usually incompletely absorbed?
Orally administered
What is bioavailability?
The % of a drug that enters the systemic circulation in an unchanged form after drug administration
How does the body get rid of the drug?
Biotransformation
What are the types of biotransformation?
- drug undergoes enzyme catalyzed transformation
- drug undergoes no transformation & is excreted unchanged
- Drug changes spontaneously into other substances without help of enzymes
Where are metabolic sites?
Liver, intestines, lungs, kidney, adrenals, skins, placenta
What are implications of metabolic sites?
Increased / decreased metabolism
decreased therapeutic effects
toxic amount of drug
What are methods of excretion?
Liver via bile
Kidney via urine
What are implications of excretion?
What is first order kinetics?
Drugs eliminated from the body at a rate dependent on the amount of drug present in the body
What is zero order kinetics?
Drugs eliminated from the body at a constant rate regardless of the concentration of drug in the body
What is a half-life?
Time required for the plasma concentration to decline by one-half after a single dose administration
Is half-life changed by the dose of the drug given?
Half life is unchanged regardless of the dose of drug given
How much of a drug concentration is gone after 2 half lives?
75%
How much of a drug concentration is gone after 3 half lives?
87.5%
How much of a drug concentration is gone after 4 half-lives?
93.8%
What is the significance of 4 half lives?
it takes 4T1/2 to reach steady state (with multiple doses) or to be eliminated (after only one dose)
What is a dose regimen?
Appropriate dosage regimen based on half life and therapeutic index
What does the loading dose produce?
a rapid therapeutic concentration in blood or tissue
(Vd x c)
What is a maintenance dose?
A dose given at appropriate intervals to maintain therapeutic concentration and effect
(Css x CI)
When a supplemental dose is given and the dose is eliminated what is the result?
Steady State (ss)
What are examples of a dose regimen?
Single dose
Continuous infusion
Intermittent dose
What is the definition of pharmacogenomics?
Study of how a person’s genes affect their response to medication
What does pharmacogenomics encompass?
The development of drug therapies to compensate for genetic differences in patients which cause varied responses to a single therapeutic regimen
