Pharm 1: Block 1 Flashcards
Define Prescription
Prescriber’s order for a specific patient
Define “Sig”
Signetur
“let it be labeled”
What are the two safety categories of prescriptions
Legend- federal requires Rx for drug prescription
OTC- considered safe for self-administration
FDA determines if a drug should be a legend or OTC based on what?
Safety Consideration
Who controls and monitors drugs considered to have abusive potentials?
DEA
Who approves what indications a drugs is used for?
FDA
Define Labeled Use
FDA approved a New Drug Authorization saying drug is safe/effective for an indication
Define Unlabeled Use
Use of a medication for an indication that has not been approved by the FDA
What is the generic name for Neurontin?
Gabapentin
PAs may be privileged to write Rxs for medication that have been approved and recommended by whom?
Pharmacy and Therapeutics Committee
What is the military’s Rx form number?
DD 1289
Rxs for children 12 y/o and younger need to include what other two pieces of info?
Age
Weight
What are the 4 drug name/classifications?
Chemical Name
Drug Name- Trade/Brand, Generic
Pharmacotherapeutic Class
Target Physiologic System
What drug name is used by the FDA and which one is used by a company/manufacturer?
Trademark= trade/brand Generic= FDA
DoD allows a __ day supply for a maintenance medication
90 days
How many refills are allowed for Schedules 2-5?
2: None
3-5: 5 x in 6mon, what ever happens first
What additional info is added to a hand written prescription for controlled substances?
Quantity of meds is written/spelled out in numeric and letters
What are 4 factors that encourage PT noncompliance?
Asymptomatic
Inc frequency
Direction difficulty
Side effects
Define ASA
Define ATC
Aspirin
Around the clock
Define HA
Define HTN
Define HOTN
Headache
Hypertension
Hypotension
Slide 24 25 26 27
Abbreviations
What is the difference between adverse drug reaction and medication error?
ADR: unexpected/unintended response to a med
ME: event leading to inappropriate medication use
Define Allergic Reaction
Immunologic hypersensitivity that occurs after medication use where the drug acts as an Ag in the body
Define Idiosyncratic Reaction
Abnormal susceptibility to a medication that is peculiar to an individual
Antihistamine causing excitement instead of sedation
Who classifies/categorizes controlled substances?
DoJ
DEA- Office of Diversion Control, Title 21 USC CSA
What are the limitations/regulations on filling a Schedule II Rx?
No Federal limit on quantity, limited by State/local law
90 day limit for matinenance
No federal time limit to fill
No refills
What happens if a pharmacist fills a Schedule II drug in an emergency situation?
May dispense quantity to adequately treat PT during emergency period
Prescribing practitioner must provide written/signed Rx w/in 7 days
What are 3 exception for when a faxed prescription can serve as an original Rx and no further verification is required?
Compounded for direct administration
Long term care facilities
Hospice
During what period of instruction is a human embryo’s growth disrupted?
Organogenesis- 3-8wks
Teratogenic agents
What does maternal alcohol abuse do to a developing fetus?
Microcephaly
What does maternal ACE inhibitor use cause to a developing fetus?
Renal function
What does maternal warfin use do to a developing fetus?
Cartilage defects
Define Category A Drug
Safe for human and baby
Define Category B Drug
No risk to fetus
Define Category C Drug
Adverse to fetus
Define Category D Drug
Evidence supporting adverse effect to fetus
Define Category X Drug
Do not give to pregnant woman
FDA required the use of what 3 subsection labeling?
Pregnancy
Lactation
Reproductive risk potential
What makes up Tiers 1 and 2 of DoD Formulary?
BCF- 1 & 2, must be carried by all MTFs
ECF- 1&2, must be carried if medical service is offered
UF Drugs- 1&2
Define Tier 3 Drugs
Non formulary drugs
Define Tier 4 Drugs
Medication is not covered, copayment reduction for required need
What is the Uniform Formulary?
Pharmaceuticals listed by therapeutic classes determined by DoD P&T committee
Define Non-Formulary Unit
Agents not selected for UF
Define Basic Core Formulary
List of pharmaceuticals required to be on local formulary
Define Extended Core Formulary
Medicatoins used to support specialized scopes of practice than the BCF
What happens if an MTF chooses to have an ECF on its formulary?
Must have all ECF medications in that class on the formulary
Define Non-Formulary
Medication that can be provided at formulary cost share if the provider supplies information showing there is a medical need/necessity
What are the phases of drug development?
Pre-clinical Phase 1-4 Pre- animal pharm/tox 1- Healthy volunteers 2- PTs w/ disease/condition 3- Large scale multi-center 4- Post-marketing surveillance
Define Pharmacokinetics
Define Pharmacodynamics
What body does to drug
What drug does to body
What do the 4 phases of pharmacokinetics encompass?
ADE
Administration
Systemic circulation
Site of action concentration
What are the 4 phases od pharmacokinetics?
ADME
What are the pharmacokinetics taken into consideration when determining dosage regimen
Bioavailability Volume of distribution Drug accumulation Clearance Elimination
What are some factors that determine drug’s access to a molecules site of action?
Route Absorption Distribution Binding Metabolism Clearance
What happens when a weak acid is placed into an acid medium?
Shift to left, suppresses ionization
What happens when a weak acid is placed in an alkaline medium?
Ionization increases
What happens when a weak base is placed into an acid medium?
Shift to left, increased ionization
What happens when a weak base is placed into an alkaline medium?
Shift to right, suppresses ionization
A drugs ability to move from an aqueous to lipid environment depends on what?
Charge
pH of solution
Define Hydrophilic
Hydro: Charged, Polar
Lipo: Uncharged
Define the Henderson-Hasselbalch equation
Relationship between ratio of acid to base
Define pKa
negative base log of the acid dissociation constant of a solution
Low= acidic
High= basic
Ph of a biologic fluid that dissolves a drug affects what two results?
Degree of ionization
Rate of transport
What happens if/when the pKa of a drug equals the pH of the surroundings?
50% ionization occurs
Define Weak Acid
H: concentration of protonated/unionized form
A: concentration of ionized/unprotonated form
Define Weak Base
BH: concentration of protonated form of base
B: unprotonated concentration
How will sodium bicarbonate effect the renal excretion of weak acids?
Increases elimination by increasing urine’s pH, turns the weak acid into unprotonated/ionized
Alkalinizing urine will have what effect on elimination?
Acidification of urine will do?
Alk: increases elimination of acidic
Acid: increases basic drug elimination
Define Bioavailability
Fraction of unchanged drug reaching the systemic circulation after oral administration
What determines/how is bioavailability determined?
Extent of absorption
First pass metabolism
What is an example of a drug that is close to 100% bioavailable?
IV drugs
What factors affect passage of drugs across biologic membranes?
Lipid-aqueous partition coefficient (ionization/non-ionized coefficient)
Specific transport
Plasma binding
Perfusion rate
____ is the primary site of drug metabolism and _____ is reduced
Liver
Bioavailability
First Pass Metabolism primarily applies to what type of drug but may limit efficacy if ?
Oral administerred
Efficacy limited if clearance by liver is large
What systemic circulation by influence overall first pass metabolism?
Enterohepatic
What are 3 ways to obtain better systemic absorption of a drug that has high first-pass effects?
Increased dose
Alternate admin route
Delayed release drug product
What are the two drug transport proteins?
Albumin
A1-acid glycoprotein
Drugs bound to ___ proteins are not active and only ____ drugs are active
Plasma
Free
Free drug is available to undergo what two processes?
Bind w/ receptor
Metabolize/eliminated
When/why is plasma protein binding important?
High plasma protein bound drugs- ibuprofen
Drugs w/ narrow therapeutic index- phenytoin
Define Drug Modeling
Describes drug distribution behavior in body by using compartmental models
What are 4 characteristics of compartmental models?
Simplification
Non-representative of single tissue
1 / 2 / 3 compartment model
Highly perfused compartments = 1 compartment
Define One Compartment Model
Simplest
Comprises all body tissues
Assumes instant distribution through body
Define Two Compartment Model
Distribution is not instant
Fist compartment- blood, and highly perfused tissue
Second- less accessible tissues
Define Volume of Distribution
Volume that drug distributes and evaluates extensive/limited distribution
“Where the drug goes in body”
What is the volume of distribution equation and parts?
Vd=Fdose/Co
F- bioavail
Dose- weight of drug given
C- concentration of drug in blood/plasma
What unit of measurement is Volume Distribution (Vd) reflected in?
L
L/kg
Define Small and Large Volume Distribution
Minimal drug distribution
Extensive drug distribution
How does plasma proteins affect volume of distribution?
Drug w/ affinity for protein in plasma will have reduced Vd, decreased plasma proteins will increase Vd
What is the major plasma protein involved in drug protein binding?
Albumin
What two structures make the BBB?
Capillaries covered in astrocytes
Endothelial cells making tight junctions
How does the placenta affect drug passage?
Lipid solubility facilitates entry
Placenta is porous, allows large hydrophilic molecules to cross which allows fetal blood levels to increase slowly
Metabolic pathways of drugs normally alter drugs in what ways?
Deactivate
Detox
Less active
What are the two major type of drug metabolism reactions?
Phase I: Non-synthetic, Cytochrome P450
Phase 2: Synthetic, Glucuronidation
Phase 1 -> Phase 2= conjugation
What are examples of Phase 1, Non-Synthetic reactions?
Oxidation
Reduction
Hydroxylations
How does Phase 1, Non-Synthetic reactions work?
Introduce function groups to molecules
Converts parent drug to polar metabolite
Causes loss of pharmacologic activity
How do Phase 2, Synthetic metabolism reactions work?
Conjugation reactions
Covalent linkage w/ functional group on parent compound
Highly polar conjugates= rapid drug elimination from body
Define Inactive Metabolite
Active compound becomes inactivated/detoxed
Metabolites that retain similar activities are retaining what part of their molecular structure?
Retain activity of parent compound
What does a metabolite with altered activity mean?
Develops different activity from parent drug
Define Bioactive Metabolites
Prodrug- inactive substance that must be converted by metabolism to become biologically active
Prodrug= inactive form
Define Cytochrome P450 Enzymes
Mixed function oxidases responsible for majority of drug metabolism
Define Cytochrome P450 System Substrate
Substance on which enzyme acts
Define Cytochrome P450 System Induction
Accelerated metabolism resulting in decreased action of inducing/co-administered drugs
Define Cytochrome P450 System Inhibition?
Reduced metabolism of substrates/co-administered drugs metabolized by specific enzyme causing increased action of co-administered drug/substrates
What system is behind most clinically important drug/drug interactions?
Cytochrome P450 System
Define Chirality
Sereoisomerism
Geometric property of molecules/ions
What are characteristics of chiral molecules?
Non-superposable on mirror image
Rectus- right
Sinister- left