Chp 2 (pharmacological principles) Flashcards
what is the chemical name vs generic vs trade?
chemical- chemical composition and molecular str, generic- shorter than chemical, used in official compediums to list drugs, trade name0 trademark name.
what is the patent life of drugs?
20 years. after this expires than other companies can make generic versions of the drug.
what does pharmaceutics mean?
study of how diff dosage forms (eg. injection, capsule influence how body metb a drug and how it affects the body)
what is pharmacokinetics?
what the body does to the drug molecules. e.g. absorption, distribution, etc.
what is prodrug?
parent drug that isn’t pharmacologically active. gets metbs to pharmacologically active metabolites. more easily absorbed.
what is pharmacodynamics?
study of what the drug does to the body d/t chem
what is the receptor theory?
assumes all drugs perform their actions @ the specific receptor sites
what are the 3 phases that affect drug activity?
pharmaceutical phase (disintegration of dosage form- ready for absorption), 2- pharmacokinetics- (absorption, distribution, etc.), pharmacodynamics
what is o Pharmacotherapeutics
ocuses on use of drugs and clinical indications for giving drugs. Defines principles of drug actions (cellular processes that change in response to the presence of drug molecules)
____ effects of drugs are often extensions of their therapeutic effects
toxic
what is pharmacognosy?
the study of natural drug resources (plants and animals)
dosage forms affect rate of what?
dissolution (dissolving of solid forms and their absorption )
what is absorption?
the movement of a drug form site of admin to bloodstream for distribution to tissues
what are some factors that affect absorption?
o Food/fuids in GI tract o Formulation o Status of absorptive surface o Blood flow o Acidity o Motility o route
what is first pass effect?
inactivation of a drug by the lvier
what are the 3 general routes of administration?
enteral, parenteral, topical
what is enteral and what are the subtypes?
absorbed thru mucosa of stomach or sm intes.
subtypes- sublingual or buccal
what does it mean when a drug has a high first pass effect?
alot of it has been inactivated by the liver. sometimes why parenteral versions of drugs have smaller doses
why do some parenteral drugs have smaller doses?
because they don’t go thru first pass effect
what are some factors that affect acidity of stomach?
time of day, age, previous ends, foods, drinks that effect absorption
anticolinergic drugs can slow down what time?
transit time- time it takes substances in stomach to be dissolved and passed into intestines
do sublingual and buccal drugs bypass the liver?
yes
can topical and transdermal also be considered parenteral?
yes but typically injections
do parennterl bypass the first pass effect?
yes
how long does it take for an IM to absorb? what is a depot drug?
• Most IM is absorbed over several hrs but depot drugs are designed for slow absorption and may be absorbed over days to several months
where are topical drugs administered?
skin, lungs, rectum, vagina, eyes, ears, nose
why is the period of time that drugs are administered an issue? whats an example of a route that does?
if they experience an adverse rxn. topical.
whats a common type of transdermal med? systemic or local? does it bypass the liver?
patch. systemic - thru a controlled rate of release. yes, by passes the liver.
what are the routes with first pass effect?
o Hepatic arterial
o Oral
o Portal venous
o Rectal (both first pass and non)
at what point of pharmacokinetics does the drug begin to by eliminated by organs ?
distribution.
during distribution- where does the drug generally go to? where are slower distribution areas?
highly vascularized areas such as heart, liver, kidney, brain. slower areas are muscle, skin, and fat
what is the most important protein that drugs bind to?
albumin
what happens if a patient has low albumin in re to toxicity?
larger fraction of free unbound and active drug- inc toxicity
what can cause low albumin?
large burns, malnourishment,
what is the unbound portion of the drug called?
free
is the bound portion of the drug pharmacologically active or inactive?
inactive
what is volume of distribution?
the theoretical vol that describes areas where drug may be disturb (ie. total body water, fat, intravascular)
will a highly water soluble drug have a large or small vol of distr and blood concentration?
small vol of distr and high blood conc
do fat soluble drugs have a high vol disturb and blood conc?
large vol of disturb and low blood concentration bc repelled by high water content of blood and more attractd to tissues
is it easy or difficult to distribute drugs to bone?
difficult, obvs
metab also known as?
biotransformation
what is biotransformation?
bichem alteration fo drug into inactive metabolite, more soluble compound or more potent metabolite.
what are the mechanisms of biotransformation that are chemical reactions/
oxidation, reduction, and hydrolysis
what organ is most responsible in metb? what enzyme is used most often?
the liver. cytochrome P450
what does the cytochrome P450 largely target?
lipid sold, nonpolar drugs which are hard to eliminate. this includes majority of meds.
what are other metb tissues?
sk muscle, kidneys, lungs, plasma, intestinal mucosa
drug molecules that are the metb targets of specific Es are called ?
substrates
what are some conditions/diseases that dec drug metb?
kidney insufficient, cardio dysfunction, genetics, obstruction jaundice, starvation and slow acetylator
what happens if there is delayed drug metb?
accum of drug in the body and prolonged action
what organ is the most reponsible for elimination?
kidney but liver and bowel also important
what are some less common organs responsible for elimination?
sweat, salivary and mammary glands
excretion is thru __,__, and ___
glomerular filtration, active tubular reabsorption and active tubular secretion
what is biliary excretion?
taken up by liver, rel into bile then excreted in feces. Once fat sol drug is back in bile they can be reabsorbed back into circ and then end up in bile again enterohepatic recirculation. Eg estrogen. This makes it have longer half life and duration of action
what is half life?
o Time it takes for half of a specific amount of a dru t be elim from body
what is steady state ?
r/t blood levels of a drug refers to physio state in which the amount of drug removed by elim i equal to amount of drug absorbed w each dose.
what is trough level?
lowest level of drug in body
what is pharmacodynamics?
study of what the drug does to the body d/t chemicals
different types of MOA?
receptor, affinity, agonist, antagonist, competitive antagonist, and noncompetitive antagonist
what is affinity
the degree to which a drug attaches and binds with a receptor
what is competitive antagonist
drug competes w the agonist for binding to the receptor. if binds theres no resposne
what is noncompetitive antagonist
drug combines w diff part of the receptor and inactive it; agonist has no effect
what are nonselective interactions vs selective interactions
selective interaction is when a drug alters physio response thru altering action of specific Es
o Nonselective interactions target cell membranes and cellular processes not Es eg CA drugs and Abx
example of maintenance therapy?
doesnt eradicate problems but prevents progression eg meds for HTN, oral contraceptives
example of supplemental therapy?
gives body substance nec to maint normal fx eg insulin or iron
example of supportive therapy?
maint integrity of body fx while pt is recovering from illness or trauma eg lytes or fluids for flu, blood after sx
what is empirical therapy?
doesn’t have scientific basis but is instead based on experience. Its admn of drug when a specific patho process is suspected based on symptoms as its been beneficial in past such cases eg acetaminophen for fever
what is therapeutic index?
is ratio of a drugs toxic level to the level that provides therapeutic benefits. Low TI means diff bet is small and has more likelihood of causing adverse rxn
if something has a low therapeutic index- what does this mean?
diff bet toxic and therapeutic level is small so more likely to cause adverse reaction
what are synergistic effects?
diff than additive effects and happens when tw drugs given together interact in a way that exceeds the predicted indiv ctions of the compounds eg 1+1=5 w barbiturates and alcohol. The opposite of this is antagonistic effect
what is an adverse drug event? what is the most common cause external to patients?
any undesirable occurrence w meds aka drug misadventure.
errors by caregivers
what is med use process?
refers to the 4 phases: prescribing, dispensing, admin, monitoring of drug therapy
what is an adverse drug reaction?
any rxn to drug thats unexpected and undesirable and occurs at therapeutic dosage
what are the 4 gen categories of ADR?
pharmacological rxn (extension of drugs normal effect on body), allergic rxn, and idiosyncratic rxn (abnormal response that is unexpected) missing one- must add
what are mutagenic effects?
peranent changes in genetic composition of living org and consist of alterations in the chromosome str, # of chromosomes or DNA. Drugs that can alter this are called mutagens. Drugs that affect genetic processes are active mostly during cell reprod (mitosis)
what are carcinogenic effects?
CA causeing
in re: pharmacognosy, plants provide what and animals provide what? give examples.
o Plants provide many weak acds and bases that are (alkaloids) eg atropine, caffeine, nicotine
o Animals are source of many hormone drugs eg estrogen from urine of pregnant mares. Heparin from horses and cows.
what do you do when someone has toxic levels of drug in system?
o Want to preserve ABCs. Next priority is preventing absorption of the toxic agent and speeding elim from body. Eg absorption from stomach w activated charcoal and laxatives to inc elim of the charcoal complex
what might you use to induce vomitting (toxic levels)
o Syrup of ipecac was used to induce vomiting but wasn’t v effective and was misuse by pts
what are other meds and things you can use to promote elimination of drugs when they are toxic in the body?
o Diuretics can be given to force elim. Acid or alkaline dieresis involves admin of weak acid or base of acidic or basic drs from kidneys eg by vit C or sodium bicarb
o Antivenin is used for snake bites which binds to the venom to dec damage
