What is the definition of pharmacology?
study of how drugs affect bio systems
Any chemical which affects biological processes is called?
Drug
What is the difference between endobiotics and xenobionics?
Endobiotics are normally produced by body and used as therapeutics and xenobiotics are not from the body (this is the majority)
What is the production, compounding, and distributions of drugs?
pharmacy
T-F–toxicology and pharmacology are roughly the same thing?
False–interrelate, but toxicology looks at the toxic effects of drugs and chemicals on the body.
What is pharmacotherapeutics?
treatment of disease with drug (as opposed to regular therapeutics)
What are drugs that are USUALLY (not always) specifically used to treat cancer? 2 names he gave us
chemotherapeutic agents or anti-neoplastic
What did the pure food and drug act of 1906 start requiring?
labeling of active ingredients
What act restricted the sale of addictive substances of abuse?
Harrison Narcotic ACt of 1914
What did the food, drug, and cosmetic act of 1938 require?
documentation of safety to the FDA and inactive ingredients to be labelled
What act created 2 classifications of drugs?
Durham-Humphrey Amendments-1951 (legend drugs and OTC drugs)
What is a legend drug?
federal law prohibits dispensing without a prescription
What act or amendment required documentation of EFFICACY?
Kefauver-Harris amendment 1962
What act replaced the Harrison Narcotic Act in 1970?
Controlled substances Act 1970
What 3 things did the controlled substances Act do?
- DEA
- Have to have license as a physician to prescribe
- Create a schedule of the drugs
What is phase I in a clinical trial?
Initial dose range & safety
In phase I…do the individuals have the disease?
No
What is a phase II clinical trial?
efficacy in disease and effective dose
What is a phase III clinical trial?
compare w/best current treatment DOUBLE BLIND
What is phase IV of a clinical trial?
post-marketing monitoring—>looking for that potentially harmful effect that only occurs 1/100,000
What is category I of OTC drugs?
safe and effective
What is Category II of OTC drugs?
not safe, not effective or both
What is category III of OTC drugs?
data inconclusive
T-F–vitamins, minerals etc. are under control of the FDA? per what act?
False
Dietary Supplement Health & Education Act 1994
Who does responsibility of the safety of dietary supplements etc. fall on? effectiveness?
the manufacturer—-no responsibility for ensuring effectiveness
What are the 3 types of names each drug usually has.
Chemical name–> Generic (official) name—> Trade Names
What is the implication of a generic drug with only one trade name?
company still has patent in effect and is the sole producer
What is the implication of a generic drug with more than one trade name?
- Different companies producing same drug
2. Same company, but different amounts or marketing strategy etc.
T-F—multiple products containing different generic drugs with the same single trade name exist?
True (according to his slide but he didn’t really explain)
What are the two main ways drug classes are grouped by?
Therapeutic use and pharmacological class
What is the pharmacological class based on?
target of action
What are 2 of the sources of drug info from manufacturers?
package inserts
physician desk reference
What are sources of technical drug info not from manufacturers—Just review don’t memorize.
American Hospital Formulary Service US Pharmacopeia Dispensing Information Facts and Comparisons AMA Drug Evals Publications Internet
What phase of drug reaction is associated with disintegration of Dosage?
Pharmaceutical phase
What phase of drug reaction is associated with absorption, distribution, metabolism and excretion of the drug?
pharmacokinetic phase
What phase of drug reaction is associated with drug receptor interaction (effect)?
pharmacodynamic phase
What are the 4 general routes of administration
enteral, parenteral, pulmonary, dermal
What route of administration has to deal with needles?
parenteral
What are the 2 types and their differences of dermal administration?
topical-site of intended use
transdermal-eventually goes systemic
There are 5 important considerations in selecting a route of administration. What are they? May just use this card for review.
Convenience Chemical Nature Extent of Metabolism Rate of Absorption Concentration at site of action
What are the 4 main advantages of oral administration?
convenient, economical, relatively safe, slow/prolonged absorption
Why isn’t oral administration always used?
HAS THE MOST PROBLEMS TOO! -irritation -destruction by acids -formation of complexes in gut -slow onset -Uncooperative patients incomplete absorption -first pass effect
What is the first pass effect?
is a phenomenon of drug metabolism whereby the concentration of a drug is greatly reduced before it reaches the systemic circulation—mainly by the liver
What is the advantage of sublingual administration?
eliminates first pass effect- avoids acids, enzymes and liver
What is the problem(2) with sublingual administration?
irritation and bad taste
What is the advantage of rectal administration?
reduces first pass effect (certain patients might be better i.e.. unconscious)
What are the 2 problems with rectal administration?
lack of compliance and inconvenience
What are the advantages (2) for subQ/intramuscular injections?
useful for proteins/peptides
can alter rate of absorption in the body
What are the 2 problems with subQ/intramuscular injections?
irritation
variable blood flow
What are the 3 advantages to intravenous administration?
easily controlled rate of administration
rapid onset of action
entire dose enters blood
What are 2 disadvantages of intravenous administration?
sterility
not for self medication
What is the advantage of an intra-arterial administration?
high dose to a specific organ
What are the 2 disadvantages of intra-arterial administration?
danger of hemorrhage
difficult technique
What is the advantage of intraspinal administration? problem?
high level into the CNS past the BBB, problem=difficult technique
What is the advantage of inhalation as an administration?
only choice for gases or volatile liquids
what are the 2 disadvantages of inhalation administration.
irritation, solids need to be fine particles
What is the advantage of dermal administration? problem?
adv= local action with minimum systemic effects problem= possible absorption and systemic effects
What is the advantage of transdermal administration? problem?
adv=convenient and prolonged delivery
problem=irritation
T-F–systemic intranasal administration is useful for peptides?
True
What is the difference between passive diffusion and facilitated diffusion?
passive has lipid solubility and facilitated need a carrier, but both are down a concentration gradient
For an acid-is the ionized form associated with the hydrogen or disassociated? For a base?
ACID=disassociated is ionized
BASE=associated is ionized
What is the henderson hasselbalch equation for acids?
pH=pKA+log[ionized]/[non-ionized]
What is the henderson hasselbalch equation for bases?
pH=pKA+log[non-ionized]/[ionized]
What is the pH partition hypothesis?
Non-ionized more lipid-soluble form of a weak acid/base crosses the biomembrane much more readily than the ionized more water-soluble form does
Does charged or non-charged particles move across a membrane easier?
non-charged
Are weak acids better absorbed at pHs below or above their pKA?
BELOW
Are weak bases better absorbed at pHs below or above their pKa?
ABOVE
What is the key difference between facilitated diffusion and active transport?
active transport needs an energy source
what is the key difference between an ABC transporter and a SLC transporter?
ABC transport is primary active transport and directly contains an ATPase, whereas SLC has an indirect energy source and works through an anti porter type system down the gradient of a solute.
What disease is caused by defect in ABC A1 transporter?
tangier disease (cholesterol)
What disease is caused by defect in ABC C2 transporter?
dubin-johnson syndrome (bilirubin)
What disease is caused by defect in ABC C7 transporter?
cystic fibrosis (chloride)
What disease is caused by defect in glutamate transport?
ALS
What disease is caused by folate-thiamine transporter defect?
megaloblastic anemia
Are ABC transporters primarily involved in efflux or influx in regards to the cell?
efflux
Are SLC transporters primarily involved in efflux or influx in regards to the cell?
influx
What are 4 factors that affect absorption of drugs from all sites? (JUST REVIEW IT)
- blood flow
- surface of administration site
- Number of cell layers
- drug concentration
What are 4 factors that affect absorption of drugs in the GI tract? (JUST REVIEW IT)
- Gastric Emptying Time
- Intestinal Transit Time
- Binding to Mucus and food
- First pass effect
Are tissues with receptors or without receptors typically considered storage sites?
without receptors—> no response but drugs usually accumulate here.
What are 4 factors that affect distribution of drugs in the body? (Just review)
- Blood Flow
- Crossing membrane barriers
- Polarity of drug
- Binding to plasma proteins
Does a drug bound to plasma proteins get out of the blood well?
No
T-F—no matter how much drug is administered for the drug that binds plasma proteins, saturation will not be reached?
False– administration of additional drug results in a more marked increase in the plasma concentration of free drug.
Can certain drugs compete with each other in regards to binding plasma proteins? consequences?
Yes—> can lead to potential dangerous side effects if both are in blood at same time.
Generally speaking what does not take place if a drug is bound to plasma proteins? [3]
no effect
no metabolism
no toxic effect
[opposite is true when it is not bound]
The blood brain barrier is made up of tight junctions between endothelial cells, what consequence in regards to drugs passing the barrier does this create?
lacks aqueous channels
must cross through diffusion or limited transporters
Do most drugs act receptor mediated or non-receptor mediated?
receptor mediated
What is the word for an all or none drug response?
quantal
What type of drug response is associated with blood pressure, plasma glucose levels, anti diabetic agents etc.?
graded drug response [as opposed to quantal which is all or none]
What is ED50?
effective dose to see results in 50% of the population OR effective dose to elicit a 50% proportion to a drug concentration
Can you measure quantal dose response in 1 individual?
No, but you can measure graded dose response in 1
CAn a lethal dose be graded?
No, must be quantal
In a graded response curve- can the curve always go up with more drug?
No- saturates and plateau
What are the key differences in regards to efficacy and potency?
efficacy-Emax is different
potency-Emax can be reached but dose amount is different
What is the potency ratio?
ED50 of drug that takes a larger dose divided by ED50 of drug that takes a smaller dose to elicit same response
That is the therapeutic index ratio?
TD50/ED50
or
LD50/ED50
[it is important to remember that when we are looking at potency, it is the same effect. however, when we are looking at therapeutic index, it is a very different effect]
Is a therapeutic index of lower than 10 safe?
No
Is a therapeutic index of higher than 500 safe?
Yes- considered very safe
What is a drug that by itself produces a response?
agonist
What is a drug that produces no response but stops other responses?
antagonist.
can the antagonist block an endogenous agonist or only other drugs?
can block both
Is an antagonist and an inverse agonist the same?
no–an inverse agonist illicits a response in the effect that it represses. antagonist don’t illicit any response by itself
What are the 3 main types of antagonists mentioned?
pharmacological
chemical
physiological
What are the 2 types of pharmacological antagonists?
competitive and non-competitive
Do pharmacological antagonists interact with receptors directly?
yes
Can adding more agonist overcome competitive antagonists or non-competitive antagonists?
competitive antagonists–>effects are reversible
Are the non-competitive antagonist effects reversible?
No- have to wait for re-synthesis of the receptor
Are partial agonists used as antagonists?
yes—they compete with the agonist and because their effects are partial they illicit a smaller effect and therefore antagonize
How do chemical antagonists act?
bond with agonist in a way that the receptor can not be activated
What type of drug only reacts with a single receptor sub-type?
receptor specific drug
What type of drug reacts with multiple receptor subtypes but favors one of them?
receptor selective drug—most drugs
What is synergistic effect?
response is greater than the sum of the 2 drugs
What is an unusual or atypical response in small % of individuals?
idiosyncratic drug response
what is an allergic response to a drug?
hypersensitivity
What is a less than expected response?
hyporeactivity
what is a greater than expected response?
hyperreactivity
what is a decreased response that takes hours to develop?
tolerance
What is a decreased response that takes minutes to develop?
tachyphylaxis
What is a decreased response to the point that there is not response?
refractoriness
What are the four basic sources of side/effects? (just think logically, not that bad)
- Chemical Properties of the drug
- Drug that interacts with multiple receptor types (dirty)
- Interact with single receptor but multiple subtypes
- Drug that interacts with single receptor but it is on many different tissues.
What is the one goal of pharmacology?
eliminate undesirable effects by increasing receptor specificity
What are the 3 main ways of terminating drug action?
redistribution, biotransformation, excretion
What are the 2 usual major effects of biotransformation?
- more hydrophilic
2. less pharmacologically active
What happens in a phase I reaction?
introduction or unmasking of OH, NH2, SH
What are the main metabolizing families for biotransformation oxidation?
CYP1, CYP2, CYP3
What are the 3 reaction types of phase I biotransformation?
Oxidation, reduction, hydrolysis
What happens in a phase II reaction?
conjugation of an endogenous polar substance [typically these are fairly large moieties]
What type of reaction do UGTs, STs, COMT, acetyltransferase, and glutathione transferases fall under?
Phase II
What is conversion of an active or toxic compound to a much less active, inactive or non-toxic compound?
detoxification
What is a drug metabolite that has significant activity?
active metabolite
What is an inactive or relatively inactive precursor that is converted by metabolism to a more active compound?
pro-drug
What is a very toxic compound produced by biotransformation of a relatively inert substance?
reactive metabolite
What does cimetidine, macrolide antibiotics, grapefruit, and proadifen do?
inhibitors of drug metabolism and therefore increase drug level
[NOTE: THIS IS A VERY COMMON SITE OF WHERE DRUG DRUG INTERACTION OCCURS]
What do ethanol, phenobarbital, phenytoin, and DDT do?
activators of drug metabolism and therefore decrease drug levels
What are the 4 major routes of drug excretion?
kidney, liver, GI, Lungs
What are 4 minor routes of drug excretion? [JUST REVIEW]
mammary glands, sweat glands, salivary glands, tear ducts
What is the primary means of terminating drug action?
excretion [mainly urine and feces]
T-F—most drugs are able to be excreted through urine and feces.
False–usually one route
What are the limitations to kidney filtration in the glomerulus?
size and protein binding
How can we alter drug excretion through excretion? [2]
increase urinary volume [diuretics]
increase blood flow to the kidney
What types of drugs readily diffuse across membranes so retention in renal tubule is limited as fluid is reabsorbed?
non-ionized, lipophilic drugs
What is one benefit of making drugs more polar through biotransformation as it relates to excretion?
Polar molecules won’t cross back into the body once in the renal tubules [or it is less likely]
How can we alter excretion for weak acids and weak basis for better excretion?
Change pH of plasma or tubule lumen
What is a competitive inhibitor of organic anion transporter?
probenecid
What is a competitive inhibitor of organic cation transporter?
cimetidine
What is the excretion pathway in the liver?
via bile into the intestine [remember same process in the liver as in kidney, but substances <200 MW are only filtered]
What is enterohepatic circulation?
reservoir created by recycling drug getting reabsorbed by intestine then going back through liver
T-F–our micro biome may take of conjugate of a drug metabolite?
True–then it may get recycled