Sympathomimetics Flashcards
Class: non-selective, direct-acting
MOA: activates alpha and beta adrenergic receptors
a1 - vasoconstriction, increases BP
b1 - increases HR, conduction/contractility
b2 - bronchodilation
Uses: cardiac arrest, DRUG OF CHOICE for anaphylaxis, asthma, COPD, hemostasis
SE: hypertension, tachycardia, ischemia, hyperglycemia
EPINEPHRINE
Class: non-selective, direct-acting
MOA: activates alpha and beta adrenergic receptors
a1 - vasoconstriction, increases BP
b1 - increases HR, conduction/contractility
b2 - bronchodilation
Uses: neurogenic shock, cardiogenic shock (last resort)
SE: extreme vasospasm, tissue necrosis, excessive BP increase, arrhythmias, infarction, reflex bradycardia; compensatory vagal reflexes tend to overcome the direct positive chronotropic effects; alpha > beta activity
NOREPINEPHRINE
Class: non-selective, direct-acting
MOA: activates alpha, beta, and D1 adrenergic receptors
a1 - vasoconstriction, increases BP (high-dose)
b1 - increases HR, conduction/contractility (medium-dose)
d1 - vasodilation in splanchnic and renal vessels (low-dose)
Uses: cardiogenic shock, HF
SE: cardiovascular disturbance, arrhythmias
DOPAMINE
Class: non-selective
MOA: activates beta adrenergic receptors
b1 - increases HR, conduction/contractility
b2 - bronchodilation
Uses: asthma
SE: cardiovascular disturbance, arrhythmias
ISOPROTERENOL
Class: alpha-1-selective
MOA: activates alpha-1 adrenergic receptors
a1 - vasoconstriction, increases BP
Uses: nasal decongestant, mydriatic, drug-induced hypotension, orthostatic hypotension, spinal shock
SE: rebound nasal congestrion, supine hypotension, stroke, myocardial infarction, piloerection, urinary retention; mydriasis without cyclopegia (OCULAR ADMINISTRATION)
Similar: PSEUDOEPHEDRINE OXYMETAZOLINE (nasal decongestant) TETRAHYDROZOLINE MIDODRINE NAPHAZOLINE XYLOMETAZOLINE
PHENYLEPHRINE
Class: alpha-2-selective
MOA: activates alpha-2 adrenergic receptors
a2 - decreases central sympathetic outflow
Uses: hypertension, cancer pain, opioid withdrawal
SE: sedation, rebound hypertension (treated by PHENTOLAMINE), dry mouth; taper use prior to discontinuation to avoid rebound hypertension
CLONIDINE
Class: alpha-2-selective
MOA: activates alpha-2 adrenergic receptors
a2 - decreases central sympathetic outflow
Uses: antihypertensive rescue drug for pregnant women, pre-eclampsia, GHTN
SE: sedation, hemolytic anemia (positive-Coomb’s test i idiosyncratic reaction)
Similar: GUANFACINE GUANABENZ DEXMEDETOMIDINE (sedative) TIZNIDINE (muscle relaxant)
METHYLDOPA
Class: alpha-2-selective
MOA: activates alpha-2 adrenergic receptors
a2 - decreases secretion of aqueous humor
Uses: gluacoma
SE: BOV, dry mouth, hyperemia, pruritis, eye discomfort
Similar:
BRIMONIDINE
APRACLONIDINE
Class: beta-1-selective
MOA: activates beta-1 adrenergic receptors
b1 - increases HR and contractility
Uses: acute HF, cardiogenic shock
SE: tachycardia, arrhythmias, tachyphylaxis (quick tolerance reaction); cardiac stress testing
DOBUTAMINE
Class: beta-2-selective
MOA: activates beta-2 adrenergic receptors (increases cAMP in lungs)
b2 - bronchodilation
Uses: DRUG OF CHOICE for acute asthma attack
SE: tachycardia, arrhythmias (in patients with concurrent COPD and heart disease or when used excessively), nervousness, restlessness, loss of responsiveness
Similar:
TERBUTALINE - preterm labor tocolysis
RITODRINE - preterm labor tocolysis
ALBUTEROL / SALBUTAMOL
Sympathomimetic of choice in ACUTE HF or SEPTIC SHOCK (desired INCREASE CARDIAC OUTPUT)
beta-1 & D1 agonist
Sympathomimetic of choice in HEMOSTASIS, DECONGESTION, and SPINAL SHOCK (desired VASOCONSTRICTION, temporary MAINTENANCE OF BP)
alpha-1 agonist
Sympathomimetic of choice in BRONCHOSPASM, PREMATURE LABOR (desired BRONCHODILATION, UTERINE SMOOTH MUSCLE RELAXATION)
beta-2 agonist
Sympathomimetic of choice in HYPERTENSION, GLAUCOMA (desired DECREASE in BP)
alpha-2 agonist
