Cholinergic Antagonists Flashcards
What does a cholinergic antagonist do?
Blocks the parasympathetic system by blocking Ach at muscarinic sites of the ciliary body and iris
What are the 5 ocular cholinergic antagonists?
STop ACH Scopolamine Tropicamide Atropine Cyclopentolate Homatropine
CNS toxicity is most likely with which ocular cholinergic antagonist?
Scopolamine - penetrates the BBB
Which ocular cholinergic antagonist has the shortest duration and the fastest mydriatic effect?
Tropicamide
What is the onset time for atropine?
60-180 minutes
What is the cycloplegic duration of atropine?
7-12 days
What are the symptoms of atropine toxicity?
Dry mouth
Dry, flushed skin
Rapid pulse
Disorientation and fever
Which cycloplegic drug has the fastest and shortest duration?
Cyclopentolate
What is the mydriatic and cycloplegic onset of cyclopentolate?
20-45 minutes
What dose of cyclopentolate is used for kids under 12 months?
0.5%
What dose of cyclopentolate is used for adults and kids over 12 months?
1.0%
Which is more potent, atropine or homatropine?
Atropine
Which cholinergic agonist is the standard for treating anterior uveitis?
Homatropine
What are the 3 reasons for the use of Homatropine in anterior uveitis?
Dilates pupil to decrease the likelihood of posterior synechiae
Reduces pain by paralyzing the ciliary and sphincter muscles
Stabilizes the blood-aqueous barrier by constricting the iris and ciliary body vasculature
What are the symptoms of anticholinergic toxicity?
Hot as a hare Red as a beet Dry as a bone Mad as a hatter Blind as a bat
