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the transmission of a drug from the site of administration to the bloodstream
adverse drug reaction
an undesirable, unexpected, and potentially dangerous response to a drug that occurs at therapeutic drug dosages
the strength of attraction of a drug to a receptor site; drugs with high affinity have a strong attraction to the receptor
a drug that interacts with a receptor, causing a response
a drug that blocks a receptor, thus blocking an agonist from binding to the receptor and activating it
the drug concentration available to bind to receptors at its target tissue or site of action; a subcategory of absorption
body surface area
the total surface area of the human body; to be used as a tool in the calculation of dosing medications
relating to the skin
a muscular area located above the armpit and 2 to 3 fingerbreadths below the acromion process used for small intramuscular injections (less than 1 mL of medication)
when the body has a physiological or psychological need for a drug
the transportation of medication to the sites of action via bodily fluids; it is influenced by the ability to travel to the site of action through the bloodstream
duration of action
the length of time that a drug’s concentration is sufficient to cause a therapeutic response
the administration of medication via the gastrointestinal (GI) tract
the elimination of drugs from the body, primarily through the kidneys
first-pass effect
a phenomenon in which an oral drug gets metabolized at a specific location in the body that results in a reduced concentration of the active drug upon reaching its site of action
the time it takes for the serum drug concentration to be reduced by 50%
health literacy
an individual’s ability to obtain, understand, and make appropriate decisions based on information to promote their health and wellness
the reason why a drug might be given
the administration of a drug into a muscle
intravenous (IV)
the administration of a drug directly into a vein
intrinsic activity
the maximal effect that can be produced by a drug
a molecule that binds to a receiving protein molecule or receptor
mechanism of action
the way a drug produces its effects on the body, or the way a drug works
medication reconciliation
the process of identifying and verifying the most accurate list of medications that a client is taking, including the drug name, dosage, frequency, and route that the client is taking
where a drug is changed into a less active or an inactive form by the action of enzymes—usually in the liver—and then is excreted in the stool or urine; metabolism prepares a drug for excretion from the body
minimum effective concentration (MEC)
the minimum concentration of a drug that produces an intended therapeutic effect
onset of action
the time at which a drug produces a therapeutic effect after drug administration
the administration of medication anywhere other than the gastrointestinal (GI) tract
partial agonist
drugs that function as either agonists or antagonists depending upon the level of the surrounding full agonist
the time during which a drug has the maximum serum concentration
the way a drug interacts with receptors, target cells, body systems, and organs to produce effects, or what the drug does to the body
the movement of a drug through the body, or what the body does to the drug
a reactive site on the surface or inside of a cell; often what happens with a drug is that it attaches itself to a receptor to elicit a therapeutic response
side effect
secondary effects produced by a drug at therapeutic doses
the administration of a drug into the adipose (fat) tissue
therapeutic effectiveness
the drug is doing what the drug is supposed to do—the most important quality a drug should have
therapeutic index
the ratio of the dose of a drug that produces a therapeutic effect to the dose that causes toxicity; sometimes known as the therapeutic window
a condition where the body adapts to a substance (drug) after repeated administration, and gradually, over time, the body requires higher doses to achieve the same initial effect (often seen in opioid use)
excessive amounts of a serum drug level in the body, usually seen when the body’s normal mechanism for metabolizing or excreting a drug is compromised
topical administration of a drug through a patch on the skin
a muscular area below the iliac crest on the lateral aspect of the thigh considered to be the safest, most preferred site for intramuscular injections

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