Drug MOA's Flashcards
ASA
in small doses blocks thromboxane a2, potent platelet aggregate and vasoconstrictor
decreased platelet aggregation
adenosine
slows conduction time through AV node, can interrupt re entrant pathways through AV node
slows sinus rate
larger doses decrease bp by decreasing peripheral resistance
albumin normal serum
exerts oncotic pressure, which expands volume of circulating blood and maintains cardiac output
albuterol
beta agonist primarily b2, relaxes bronchial smooth muscle, resulting in bronchodilation, also relaxes vascular and uterine smooth muscle, decreases airway resistance
amiodarone
multiple effect on NA K and CA channels
prolongs action potential, refractory period
ventricular automaticity K
slows membrane depolarization and impulse conduction NA
negative chronotropic activity in nodal tissue, rate reduction, and antisympathetic acticity CA and Beat blockade
dilates coronary arteries DA Alpha blockade
atropine pharmacological
blocks action of ACH as competitive antagonist at muscarinic sites in smooth muscle secretory gland, and CNS
blocks parasympathetic response allows sympathetic to take over
increase in cardiac output, drying of secretions
atropine clinical
CV: +chrono, +dromo, slight +ino, increased cardiac output
Resp: decreased mucus production, bronchodilation
GI: decreased secretion, motility
GU: decreased urinary bladder tone
Misc: mydriasis decreased sweat production
bumetanide
inhibity electrolyte reabsorption in ascending loop of henle leading to diuresis
calcium chloride
increases ECF ICF calcium levels stimulates release of catecholamines \+ino may enhance ventricular automaticity inhibits effects of adenosine on mast cells
calcium gluconate gel
neutralizes hydrofluoric acid to form calcium fluoride
helps stop fluoride ion from penetrating tissue and bone
activated charcoal
pharmacological: physical binding of toxins from GI tract
clinical: prevents/reduces systemic absorption of toxins
cimetidine
competitively inhibits action of histamine at h2 sites of parietal cells decreasing gastric acid secretion
dexamethasone sodium phosphate
improves lung function and myocardial performance
decrease in pulmonary edema, relaxation of bronchospasm
D50
pharm: aerobic metabolic substrate
clinical: reverses CNS effects of hypoglycemia by rapidly increasing serum glucose levels
provides short term osmotic diuresis
diazepam
works on parts of limbic system, thalmus, and hypothalamus producing calming effects increases seizure threshold transient analgesia amnesic sedative
diltiazem
pharm: inhibits calcium ion influx during cardiac depolarization, decreases SA and AV conduction and dilates coronary and peripheral arteries and arterioles
clinical: slows rapid ventricular rate associated with a-fib and flutter, reduces coronary and peripheral vascular resistance
diphenhydramine
blocks histamine receptors
decreased capillary permeability and decreased vasodilation, prevention of bronchospasm
some anticholinergic effects
dopamine 1-2 mcg
dopaminergic receptors to stimulate cerebral renal and mesenteric vasodilation, HR BP usually unchanged
dopamine 2-10 mcg
B1 receptors, increased cardiac output, modest increase in SVR
dopamine 10-20 mcg
a adrenergic effects, renal mesenteric peripheral arterial and venous vasoconstriction, marked increase in SVR, pulmonary vascula resistance, further increased preload
dopamine >20 mcg
effects similar to norepi, may increase HR and o2 demand to undesirable levels
epi pharmacological
A&B agonist, A-increased SVR, B1- +inotropic and chronotropic increases automaticity and irritability
B2- bronchodilation, dilation of skeletal vasculature
epi clinical
cardiac arrest- increases cerebral and myocardial perfusion pressure, increases bp, increases electrical activity in myocardium
bradycardia- +chrono, increases bp,
reverses s/s of bronchospasm and anaphylaxis
etomidate
produces hypnosis rapidly causing CNS depression and anesthesia, no analgesic effect
fentanyl citrate
alleviates pain by acting on pain receptors in brain, elevates pain threshold
depresses CNS, depresses brainstem respiratory centers
increases venous pooling, vasodilates arterioles thus reducing preload and afterload
furosemide
pharm: inhibits NA K chloride reabsorption in ascending loop of henle, venous pooling and decreased afterload
clinical: diruesis
glucagon pharmacological
acts only on liver glycogen, converting it to glucose, counteracts effects of insulin, relases gi smooth muscle causing dilation and decreased motility
cardiac inotrope
glucagon clinical
may reverse hypoglycemia within 4 mins
hydroxocobalamin
binds to cyanide ions
ipratropium bromide
anticholinergic agent, antagonizes action of ACH
ketamine
produces dissociative anesthesia
minimal cardiac depression
bronchodilator, respiratory stimulation frequently seen
lidocaine
decreases automaticity by slowing rate of spontaneous phase 4 depolarization
terminate re-entry by decreasing conduction in re-entrant pathways
increases v-fib threshold
lorazepam
high afinity for GABA benzo receptor without displacing GABE
exerts tranquilizing action on CNS
magnesium sulfate
decreases myocardial irritability and neuromuscular irritability
reduces ventricular irritability
inhibition of muscular excitability
solu-medrol
thought to stabilize cellular and intracellular membranes
midazolam
CNS effects mediated through GABA
acts on limbic, thalamic, and hypothlamic levels of CNS producing anxiolytic, sedative, hypnotic, and anticonvulsant effects
capable of producing all levels of CNS depression, from mild sedation to coma
morphine
acts on pain receptors in brain, elevates pain threshold
depresses CNS, respiratory centers
venous pooling, vasodilates arterioles, reducing preload and afterload
histamine release
nitro
smooth muscle relaxant on vascular, uterine, bronchial, and intestinal smooth muscle decreases preload and afterload coronary artery vasodilation increases blood flow to myocardium decreases myocardial o2 demand
norepi
stimulates b1 and a1 receptors causing vasoconstriction, increased bp, enhanced contractility and decreased heart rate
ondanestron
selectively blocks serotonin 5-HT3 receptors located in CNS at chemoreceptor trigger zone and in peripheral nervous syste on nerve terminals of vagus nerve
oxytocin
binds to oxytocin receptor sites on surface of uterine smooth muscles, increases force and frequency of uterine contractions
propofol
produces effects by positive modulation of GABA through ligand-gated GABA receptors
sodium bicarbonate
buffers H+ and increases PH
succinylcholine
combines with cholinergic receptors of the motor end plate to produce depolarization hydrolyzed by ACHe
vasopressin
causes vasoconstriction of peripheral, cerebral, pulmonary, and coronary vessels
verapamil
blocks calcium ion influx results in negative inotropy
coronary and peripheral vasodilation
slows conduction and prolongs refractory period in AV node
slows SA discharge
in summary, decreases myocardial contractile force and slows AV conduction
