intro to pharmacology Flashcards
what is pharmacodynamics?
how drugs affect the body
what is pharmacokinetics?
how the body effects drug
what are drugs derived from?
- micro-organisms
- plants
- animals
- minerals
- synthesised in labs
what are the names of drugs?
chemical, generic, trade/brand name
what is a chemical name?
description of chemical composition, atomic and molecular structure
what is a generic (non-proprietary) name?
abbreviated, name given by manufacturer to first develop
what is a trade (proprietary)/ brand name?
selected by company selling, protected by trademark
what is the enteral route?
drug administration through an enteral tube
what two routes of drugs pass through first-pass metabolism?
oral and enteral
what are some advantages of the oral route of drug administration?
- costs less
- non-invasive
- pain-free
- good patient compliance
what are some disadvantages of the oral route of drug administration?
- requires patient compliance
- patient must be conscious and cooperative
- takes longer
what is sublingual administration?
drug placed under the tongue to dissolve
what is buccal administration?
drug placed between cheek and gum
why do buccal and sublingual administration rapidly absorb?
due to capillaries of the mucous membrane rather than being processed by GI tract
what does the parenteral route mean?
any non-oral method
what are the most common parenteral routes?
intravenous (IV), intramuscular (IM), and subcutaneous (SC)
what are some advantages of the parenteral route of drug administration?
- IV and intraarterial routes provide immediate onset
- avoids first-pass metabolism
- problems with patient cooperation and conscious state can be voided
what are some disadvantages of the parenteral route of drug administration?
- can be painful
- onset can be rapid
- more expensive
- requires accurate dosage
what is the inhalation (pulmonary) route?
drugs administered by gas or fine mist
what is the topical drug route?
applying the drug to the skin or mucous membrane
what is drug absorption?
the process a drug will go through as it moves from the site of administration to the systemic circulation
what are the factors that affect drug absorption?
- route of administration
- tissue surface area and thickness
- blood supply at site of administration
- solubility of drug
do lipid-soluble or water-soluble drugs have rapid absorption?
lipid-soluble
what is drug distribution?
once the drug has reached systemic circulation it can be distributed to various body compartments
what is drug distribution the process of?
irreversible transfer of a drug between one location and another
what does the movement of a drug to body tissues depend on?
- solubility
- cardiovascular functioning
- perfusion of area
- pH of area
what is metabolism?
process where drugs are broken down into substances more easily eliminated
what is the most important site of drug metabolism?
liver
what are the factors affecting metabolism?
- genetics
- enviro
- age and gender
- disease states
what is bioavailability?
refers to the amount of drug available to exert a pharmacological effect
what is bioavailability the proportion of?
% of administered drug that reaches systemic circulation
what is hepatic first-pass metabolism?
drugs administered orally pass through the GI Tract before being absorbed through GI mucosa into the blood of surrounding capillaries
where is excretion primarily taking place?
kidneys
what is excretion?
the irreversible loss of drug from the body
what is elimination?
the irreversible loss of drug from the plasma
what is the therapeutic range?
the range of concentration of a drug having a high probability of producing the desired therapeutic effect and low probability of toxic effects
what does the therapeutic range lie between?
minimum effective concentrations and minimum toxic concentrations
what is drug half-life?
defined as time taken for drug concentration to be reduced by 50% from its max concentration
what dies a drug half-life tell us?
- how quickly a drug is eliminated from plasma
- how often we need to administer to keep within therapeutic range
what is the minimum effective concentration?
when there is enough in plasma to begin exerting pharmacological
what is the onset of action?
time at which min, effect concentration is reached
what is the termination of the drug effect?
concentration has dropped below min effective concentration, no longer has a therapeutic effect
what is the duration of drug action?
time between min effective concentration and termination
what are the drug’s molecular targets?
- carrier proteins
- ion channels
- enzymes
- receptors
how do drugs bind to carrier proteins?
bind to prevent carrier protein from moving molecules into cell
how do drugs act on ion channels?
binding to channel causing the channel to open or blocking channel
what are the two main types of drugs that affect enzymes?
competitive or non-competitive inhibitors
what is a competitive inhibitors?
drug binds to active sites and substrate cant bind
what are non-competitive inhibitors?
binds to enzymes and changes the shape preventing substrate binding, enzyme is destroyed
what are the types of drugs that bind to receptors?
agonist and antagonist
what does an agonist do?
initiates or enhances normal responses
what does an antagonist do?
blocks normal response
what is hypersensitivity to a drug?
body’s immune system shows an exaggerated response to a drug perceived as a foreign substance
what is an adverse drug reaction?
unintended and/or undesirable effect
what are the predisposing factors of an adverse reaction?
- age
- gender
- dose
- polypharmacy
- history
- genetic factors
what is polypharmacy?
taking multiple different medications
what is drug interactions?
occurs when the pharmacological effect of one drug is altered by another
what is drug contraindications?
a factor that makes the administration of drug undesirable or dangerous
what are factors that can make a drug contraindications?
- patient status
- current disease state
- drug therapy with potential for interaction or adverse reaction
what is drug transfer?
any drug given to a pregnant women may reach the fetus via circulation or be transferred to a neonate via breastmilk
what are the factors contributing to drug transfer?
- drug properties and dosage
- gestational age of fetus
