Pharm final 2 Flashcards
The inventor of the drug
Brand name
ED50 is the dose of the drug that produces
An effect in 50% of the population
TD50 is the dose of the drug that produces
Toxicity in 50% of the population
Formula for therapeutic index
TD50/ED50
Larger TI means the drug is
Safer
If a drug has a low TI, then there’s only a __ gap between what’s effective and what’s toxic
Small
With a Los TI, if the dose is off by even a small amount you could have
Toxicity
2 we’ll know drugs with low TI
Warfarin and phenytoin
If switching from generic to brand name, you need to be careful because
The potency could vary between the two
Drugs take something the body already does and alters it, but it doesn’t
Gives new functions
Process of a drug has three parts
- Delivered to tissue
- Effect on tissue
- Eliminated from body
Pharmacokinetics
What does your body do to a drug
4 parts of pharmacokinetics (similar to the drug process slide but little more details)
Absorption
Distribution
Biotransformation
Excretion
Absorption is the site of administration to
Plasma
Distribution is plasma to site of action and
Other sites too because drugs are stupid and don’t know exactly where to go
Biotransformation is ___ altering the drug
Chemically
Excretion is
Removal of drug
Word for “how does the drug work”
Pharmacodynamics
What does your body do to a drug
Pharmacokinetics
Phrase describing that the form in which the drug is taken can impact the pharmacokinetics
Pharmaceutical phase
Pharmaceutical phase aka
Route and form
Pharmaceutical phase doesn’t change what the drug ___ but it changes the speed at which it works
Does
Examples of drugs that work by targeting enzymes
ACE inhibitors and aspirin
Examples of drugs that work by altering cell membrane activity
Local anesthetics
Examples of drugs that work by targeting receptors
Antihistamines and beta blockers
Examples of drugs that work by neutralizing small molecules
Antacids
Absorption, distribution, and elimination depend on the ability of a drug to cross the
Cell membrane
__ soluble drugs cross the membrane faster
Lipid soluble
Most common way that drugs move across the cell membrane
Diffusion
Diffusion is driven by
Concentration gradients
How much of the active drug is available to tissues after being administered
Bioavailability
IM has a ___ bioavailability than oral
Higher
In which part of the 4 parts of Pharmokinetics does the the drug exert its effects
Distribution
During biotransformation, the body chemically alters the drug in order to ___ it
inactivate it
Does pH affect absorption
Yes
Weak acids are better absorbed in ___ environments
acidic
Bases are better absorbed in ___ environments
basic
Most drugs are best absorbed by which organ
small intestine
99% of the time, higher drug concentration means ___er absorption
higher
constant % of the drug released at set intervals
1st order pattern
constant amount (i.e. in milligrams) released at set intervals
0 order pattern
An example of 0 order is the use of __ ___ capsules
time released capsules
Enteral route is anything to do with the _ _ tract
G I
Enteral route is not the quickest or most ___
reliable
Stomach has no significant
absorption
Not even __ is absorbed in the stomach even though it’s acidic
aspirin
Rectal administration is good because is very ___ but bad bc it has small ___
vascular, surface area
Another advantage of rectal is that it bypasses the
first pass effect
An important concern of IV is that you don’t go
too fast
Intrathecal is aka ___ aka ___ space
spinal aka subarchnoid space
For an intrathecal aka spinal you need to monitor
BP
Medication delivered by an epidural most travel through the
meninges
Effects of an epidural are ___er than a spinal
slower
Medication delivered by the ears, eyes, skin, nasal mucosa
topical
One factor effecting distribution is __ __ binding
plasma protein
Some drugs have a high affinity for binding with
protein
If a drug is stuck to a protein it can’t get to the
tissue
2 drugs that almost completely bind to protein
warfarin and diazepam
Being bound to a protein is ___ (it changes)
dynamic
Drugs that bind to protein have a ____er duration of action. The protein slowly releases the drug.
longer
You have a drug that’s bound to protein. You add a 2nd drug that also binds. This causes some of the 1st drug to
release from the protein
Only __ soluble substances can cross the BBB
lipid soluble
Pregnancy category A
safe for pregnant women
Pregnancy category X
unsafe for pregnant women
Biotransformation inactivates a drug by making it more
water soluble
The water soluble a drug is the more easily it is
eliminated
A series of enzymes in the liver used for eliminating drugs
p450
p450 enzymes can be ___ed or ___ed by certain drugs
inhibited or induced
The basis for a lot of drug interaction is the __ enzyme
p450
Metabolism is a synonym for
biotransformation
A higher dose is needed for oral medication because of the
first pass effect
major organ of excretion is
the kidneys
With ethanol, once you reach saturation level
only a set amount can be excreted at a time
A saturation level, ethanol kind of follows a __ ___ pattern
0 order
Urinary __ can be altered to enhance excretion of poisons or medications taken in toxic doses
pH
To enhance excretion of an acid, make environment more
basic
The time it takes to reach the MEC (minimal effective concentration)
Onset of action
The most stable blood levels will be accomplished with
IV
__ frequent dosing gives you more extremes in the blood levels
Less
The frequency of dosing is partially determined by
how much the blood levels can fluctuate before getting close to toxic levels or below the MEC
the study of substances that interact with living systems through chemical processes
pharmacology
the 2 major branches of pharmacology
Medical, Toxicology
any substance used in the diagnosis, cure, treatment or prevention of a disease
drug
A drug usually has 3 names
chemical
generic
trade/brand
With some exceptions, most FDA-approved generic drugs are ___ equivalent to their brand name counterparts
therapeutically
interaction between drug and body; absorption, distribution, biotransformation, and elimination
pharmacokinetics
interaction between drug and body; practical importance in designing a drug regimen for a patient
pharmacokinetics
interaction between drug and body; concerned with the mechanism of action of drug on the tissue
pharmacodynamics
interaction between drug and body; receptor theory
pharmacodynamics
interaction between drug and body; various drug forms influence pharmacodynamics and pharmacokinetics
pharmaceutical phase
the lipid bilayer prevents movement of highly __ or __ soluble molecules
polar or water soluble molecules
term used to describe the extent of absorption
bioavailability
refers to the percentage of active drug substances absorbed and available to target tissues follow administration
bioavailability
bioavailability of IV and IM
100%
bioavailability of oral
20%
drugs classified as weak acids get absorbed more readily in __ pHs
acid pHs
Constant % of drug absorbed over time
1st order
Constant amount of drug absorbed over time
0 order
not the quickest or most reliable route
oral/enteral
gastric absorption is not
significant
3 disadvantages of intravenous high __, ___y, and ___y
high cost
difficulty
irreversibility
advantages of intravenous are rapid onset, large __, and use of ___ drugs
large amounts can be given
used of irritant drugs
5 parenteral routes
subcutaneous IM IV intrathecal epidural
Topical administration includes eyes, ears, skin, and
nasal mucosa
Distribution is affected by lipid solubility, regional blood flow/cardiac output, and ___ __ binding
plasma protein binding
drug-protein complex is not biologically active because it’s too large to
cross the plasma membrane by diffusion
bound drugs have a ___er duration of action
longer
high protein binding increases the potential for __ effects
toxic effects
barriers to distribution include the BBB and
placenta
pregnancy category; adequate well-controlled studies in pregnancy have not shown an increased risk of fetal abnormalities (prenatal vitamins, insulin)
A
pregnancy category; animal studies have revealed no evidence of harm to the fetus but no adequate studies have been done in pregnant women OR animal studies have shown an adverse effect but studies in pregnant women have failed to demonstrate risk to the fetus (penicillin, acetaminophen)
B
pregnancy category; animal studies have shown an adverse effect but no adequate studies have been done in pregnant women OR no studies have been done in animals or humans (antihypertensives, corticosteroids)
C
pregnancy category; studies in pregnant women have demonstrated a risk to the fetus, however, the benefits of therapy might outweigh the potential risks (ACE inhibitors, alcohol)
D
pregnancy category; studies in animals or humans have demonstrated positive evidence of fetal abnormalities or risks. The use of this product is contraindicated in women who are or may become pregnant
X
chemically inactivating a drug by making it more water soluble
biotransformation
biotransformation chemically inactivates a drug by
making it more water soluble
biotransformation allows the drug to be eliminated via the
kidneys
biotransformation occurs primarily in the
liver
biotransformation occurs primarily in the liver via the cytochrome
p450
the cytochrome p450 enzyme is kind of the source of
drug interactions
factors that cause variation in rate of metabolism:
impaired __ __
a__
g_____
impaired liver function
age
genetics
during passive tubular reabsorption, __ soluble drugs move back into the blood while __ soluble drugs stay in the urine
lipid (move back to blood)
water (stays in urine)
during __ __ __, pumps for organic acids and bases move drugs from blood to urine
active tubular secretion
urinary __ can be manipulated to promote excretion of poisons or medications taken in toxic doses
pH
aspirin poisoning can be treated by ___ing urinary pH
increasing (making it basic)
time at which no drug effect can be seen
termination of action
___ of action is the time interval during which a therapeutic response can be seen
duration of action
minimal concentration required to elicit a therapeutic response
minimal effective concentration
time it takes to eliminate 1/2 of a given concentration of a drug
t 1/2
primary dose, given to reach a desired concentration quickly
loading dose
the maintenance dose and time interval are chosen to minimize wide variations in ___ while maintaining a ___ dosing schedule
concentration
workable
dosing interval is the
time between doses
the duration of action only includes the time that the drug is having a ___ effect
therapeutic effect
active site at which a drug interacts
receptor
drugs that bind to receptors and mimic the effects of the endogenous compound
agonists
drugs that interfere with the binding of the endogenous agonist
antagonist
the concentration of a drug needed to produce 50% of the maximal effect (EC50)
potency
refer to the maximal effect of the drug
Efficacy
example of sympathetic neurotransmitter
Norepi
example of parasympathetic neurotransmitter
Acetylcholine
sympathetic effect; heart rate
increase (B1 receptors)
sympathetic effect; blood vessels
a - constricts
B2 - dilates
sympathetic effect; intestinal secretions
decrease
sympathetic effect; GI motility
decrease
sympathetic effect; sweat glands
increase
sympathetic effect; pupils
a1 - dialate
sympathetic effect; bronchioles
B2- dilate
sympathetic effect; bladder wall
relaxation (urinary retention) a1
sympathetic effect; lipolysis
increases B1 (increases so that you can use the energy)
parasympathetic effect; heart rate
decrease
parasympathetic effect; blood vessels
no change
parasympathetic effect; intestinal secretion
increase
parasympathetic effect; GI motility
increase
parasympathetic effect; sweat glands
no change
parasympathetic effect; pupils
constriction
parasympathetic effect; bronchioles
constriction
parasympathetic effect; bladder wall
constriction (voiding of urine)
parasympathetic effect; Lipolysis
no change
parasympathetic system is associated with ___ receptors
muscarinic
Synthesis of NE
___ ….. L-DOPA ….. ___ ….. NE ….____
tyrosine ….L-DOPA …. dopamine ….. NE ….. epinephrine
MAO stands for mono __ __
mono amine oxidase
COMT stands for catechol - O - methyl ___
transferase
DA is short for
dopamine
Parkinson’s disease is progressive deterioration of neurons that are supposed to make
dopamine
To help with Parkinson’s, ___ is given because it can cross the BBB and then start the pathway to dopamine
L-DOPA can cross the BBB
Imbalance in __, __, and maybe __ are linked to depression
serotonin, NE, and maybe DA
Tricyclic antidepressants work by blocking the __ pump. This increases the amount of __ in the synapse
block the amine pump, increases NE in the synapse
Prozac only effects levels of
serotonin
Prozac is an __
SSRI
SSRI stands for
selective serotonin reuptake inhibitor
MAO inhibitors knock out mono amine oxidase, which causes
increased NE
5 classes of drugs that affect the ANS
Sympathomimetics Sympathetic blockers Parasympathomimetics Parasympathetic blocks Ergot Alkaloids
2 kinds of sympathetic blockers
B blockers
a blockers
2 kinds of Parasympathomimetic
Direct acting
Acetylcholinesterase inhibitors
Have some properties related to ANS, but not a perfect fit
Ergot alkaloids
2 kinds of Sympathomimetic drugs
Direct and indirect
Direct sympathomimetic drugs are a___s of the SNS
agonists of the SNS
examples of Direct acting sympathomimetic drugs
Epi, Albuterol, Phenylephrine
Indirect sympathomimetics have the same result as direct but use a different
mechanism
Indirect sympathomimetics do not act as ___ agonists
receptor agonists
Epi activates both the a and B receptors which makes it
nonspecific
Epi effects which part of the nervous system
Sympathetic nervous system
Epi (and other nonspecific sympathomimetics) effect on HR
increase
Epi (and other nonspecific sympathomimetics) effect on BP
varies (low dose lowers BP, high dose raises it. Medium does gives no change)
Epi (and other nonspecific sympathomimetics) effect on bronchodilation
increase
Epi (and other nonspecific sympathomimetics) effect on insulin
decrease
Epi (and other nonspecific sympathomimetics) effect on GI
decrease
Epi (and other nonspecific sympathomimetics) effect on urinary retention
increase
Epi (and other nonspecific sympathomimetics) effect on wakefulness and anxiety
increase
The effectiveness of Epi (and other nonspecific sympathomimetics) depends on being able to cross the
BBB
Epi (and other nonspecific sympathomimetics) effect on arterioles in the lungs
constrict
Epi (and other nonspecific sympathomimetics) on appetite
decrease
Clinical uses: Asthma Anaphylactic Shock ATHD Cardiac arrest Ocular surgery Adjunct with local anesthetics Premature labor nasal docongestant
Epinephrine (and other nonspecific sympathomimetics)
Toxicity: Tachycardia Severe hypertension Cerebrovascular hemorhage Arrhythmias
Epi (and other nonspecific sympathomimetics)
