PHARMACODYNAMICS Flashcards
“what a drug does to
the body”
PHARMACODYNAMICS
All but a small number of
drugs interact with specific
sites called?
receptors.
bind
to the receptor and prevent the
cell from producing an effect.
–May block the action of another drug.
Antagonists (blockers)
a selective beta-blocker
blocks beta- 1 receptors in the heart,
reducing the heart rate;
Propranolol
blocks H-2 (histamine)
receptors in the gastrointestinal tract,
reducing gastric acid and promoting
healing of duodenal and gastric ulcers.
Ranitidine
bind to
the receptor on the cell membrane
and act on the cell through the
receptor to produce a
pharmacologic effect.
Agonists (activators)
blocks alpha-1 receptors in
blood vessels, producing vasodilation.
Used in treatment of hypertension.
Doxazosin
binds to and activates beta-2 receptors in the
bronchiolar smooth muscles,
producing bronchodilation / for asthma
Salbutamol
stimulates alpha-2 receptors
in the brain stem, thus reducing the
sympathetic nervous system outflow.
Used in hypertension.
Clonidine
for bradychardia // blocks the effect of acetylcholine, causes drymouth
Atropine
is used in the treatment of dementia
to increase levels of acetylcholine in the brain.
Galantamine
drugs are strong anti-emetics
5-HT antagonists,
The ability of a drug to produce a
response when it binds to a receptor
Potency
The ability of a drug to produce a
response when it binds to a receptor
Efficacy
The ability of a drug to combine with one
particular type of receptor. Examples of
receptors: acetylcholine, histamine and
adrenoreceptors.
Specificity
The relationship between a drug’s
desired therapeutic effects and its
adverse effects (margin of safety)
Therapeutic Index
the action of one
drug is increased by the
presence of a second drug
*Potentiation, or synergy
occurs when the action of
one drug reduces or blocks
the effect of a second.
antagonistic effect
Factor indicating that the
use of a particular drug
will cause harm.
Contraindications
expected effect
that may or may not cause harm.
Side effects
Harmful
and unexpected. It may be
seen as an effect in any organ.
Adverse effects
The ability of a drug to attack only
those systems found in foreign
cells i
selective
toxicity.
occurs
when the body recognizes the
drug as foreign and responds
by histamine release.
allergic reaction
a decision-making,
problem-solving process—to provide efficient
and effective care.
*nursing process
