sympathetic pharmacology
adrenoceptors
three main types
Alpha
Beta
Dopamine
a-1 prostate
a-2 postsynaptic CNS
B-1 heart
B-2 lungs
D-1
D-2
D-3
effects of sympathomimetics
mimics fight or flight response
increase heart rate, bronchodilation, and wakefulness and alertness
clinical effects
eye
a-2 agonist (brimonidine) increase outflow of aqueous humor
cardiovascular
a-1 agonist midodrine causes peripheral vasoconstriction
B-1 agonist dobutamine and isoproterenol have positive chronotropic and inotropic effects
respiratory system
beta agonists cause bronchodilation
CNS
a-2 agonist (clonidine) decrease sympathetic tone and blood pressure
indirect acting agents that increase levels of norepinephrine include tricyclic antidepressants and amphetamines
uterus
B-2 agonist terbutaline relaxes pregnant uterus to stop premature labor
anaphalaxis
severe allergic reaction
bronchospasm, mucous membrane congestion, hypotension
epinephrine administered via injection is treatment of choice
activated alpha, B-1, and B-2 receptors
adrenergic blockers
adverse effects
alpha blockers
dizziness and orthostatis hyotension
beta blockers
bradycardia, coolness in hands and feet, mild sedation, vivid dreams, depression, worsening asthma, erectile dysfunctions