Name: Clonidine (Catapres)
Class: Centrally Acting Antiadrenergic Agent/Opioid Withdrawal Suppressant
Mechanism: Stim. inhib. a2 receptors in central cardiovasc pathways involving EPI or NE. a2 are G-protein coupled to inhibit adenylyl cyclase ®
¯ cAMP ® ¯ central symp. activity.
Absorption: Oral, transdermal.
Dist.: Acts at medullary and spinal sites.
Metabolism.:
Excretion, t½:
Toxicity/S.E.s: Prominent sedation, dry mouth, depression in those so inclined, constipation. S.E.s may be reduced by transdermal admin. May potentiate actions of other CNS depressants. Rebound hypertension, nervousness, insomnia if w/drawn too quickly.
Utility: Treat hypertension. DOC for treating opioid w/drawal. No abstinence synd. when withdrawn.
Special Features: Direct a2 activation. Very potent (<0.5 style=""> CV reflexes remain intact; normal homeostatic responses to exercise are maintained.