Term
-What are the indirect-acting antiadrenergic agents?
-What are the 2 types? |
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Definition
-drugs that prevent the activation of peripheral adrenergic receptors, but by mechanisms that do NOT involve direct interaction with peripheral receptors
-adrenergic neuron-blocking agents (decrease NE release)
-centrally acting a2 agonists (reduce impulses along sympathetic nerves) |
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Term
-What are centrally acting a2 agonists?
-How do they work? and what are the effects similar to?
-Whats the primary use?
ex? |
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Definition
-Type of indrect-acting antiadrenergic agent
-Reduce firing of sympathetic neurons, similar effects to those of the direct-acting adrenergic receptor blockers
-HTN
-clonodine, guanfacine, methyldopa |
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Term
Clonidine: mechanism of antihypertensive action?
-pharm effects?
-therapeutic uses?
-adverse effects?
-pregnancy? |
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Definition
-selective activation of a2 receptors in CNS
-reduces sympathetic outflow to blood vessels and heart
-bradcardia and decrease CO, minimal ortho hypotension
-uses: hypertension and SEVERE PAIN
-adverse: drowsiness, dry mouth, REBOUND HTN...must withdraw slowly over 2-4 days!!
-contraindicated |
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Term
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Definition
-similar to clonidine (centrally active a2 agonist, reducing impulses along nerves)
-HTN, ADHD |
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Term
Methyldopa: MOA?
-pharm effects?
indications?
Adverse effects?
pregnancy? |
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Definition
-not really a centrally active a2 agonist (reducing impulses along nerves) but can be taken up into the brainstem and converted into a2 agonist
*this will result in blockage of NE release
-lowers BP by ACTING AT SITES WITHIN CNS
-vasodilation, not cardiosuppression
-lowers bp in supine and standing subjects
-for HTN
-adverse: positive coombs' test and hemolytic anemia
-hepatotoxicity
-xerostomia, sexual dysfunction, OH, and CNS effects
-CLASS B in preg! tradition DOC for htn women in pregnancy |
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Term
Adrenergic Neuron-blocking agents: MOA?
ex? |
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Definition
-type of indirect acting antiadrenergic agent
-act presynaptically to reduce the release of NE from sympathetic neurons
-Reserpine (only agent) |
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Term
Reserpine: MOA?
-what does it resemble?
-What an it deplete?
-pharm effects? (including CNS)
-adverse effects?
-therapeutic uses? |
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Definition
-adrenergic neuron-blocking agent
-depletion of NE from postganglionic sympathetic neurons
-First it displaces NE from neuron exposing it to MOA enzyme for rapid destruction
-secondly it suppresses the syntheses of NE (bc it blocks uptake of dopamine)
-beta blockade
-depletion of transmitters (serotonin, catecholamines)
-slows HR and reduces CO, decreases alpha activation which causes vasodilation...=decrease in BP
-CNS-sedation and state of indifference
-principle: HTN (but not a preferred drug), psychotic states (not preferred)
-DEPRESSION, bradycardia, OH, nasal congestion, GI problems |
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