copyright © 2015 cengage learning® chapter 13 autonomic nervous system drugs
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Copyright © 2015 Cengage Learning®
Chapter 13Autonomic Nervous System Drugs
Copyright © 2015 Cengage Learning®
Introduction• Autonomic nervous system (ANS)
– Automatic, self-governing, or involuntary• No conscious control
– Divided into sympathetic (alert system) and parasympathetic nervous system (resting and digesting system)• Neurotransmitters: chemical substances released
at nerve endings within these systems to transmit nerve impulses
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Introduction (cont’d.)• Drugs that affect function of the autonomic
nervous system– Adrenergics – Adrenergic blockers – Cholinergics – Cholinergic blockers
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Introduction (cont’d.)• The following slides discuss various
autonomic nervous system drugs– Refer to the chapter for specific actions, uses,
side effects, contraindications, cautions, and interactions of each
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Adrenergics• Sympathetic nervous system
– Emergency system used to mobilize the body for quick response and action
– Key words: fright, fight, or flight• What are adrenergics?
– Drugs that mimic the action of the sympathetic nervous system
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Adrenergic Blockers• Drugs that block the action of the
sympathetic nervous system – Most commonly used drugs in this category
are the alpha- and beta-adrenergic blockers, or alpha-blockers and beta-blockers• Alpha-adrenergic blockers are discussed in
Chapters 15 and 25• Prototype of the beta-adrenergic blockers is
propranolol (Inderal)
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Cholinergics• What do parasympathetic nerve fibers do?
– Synthesize and liberate acetylcholine as the mediator
• What are cholinergics? – Drugs that mimic the action of the
parasympathetic nervous system
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Cholinergic Blockers• What are cholinergic blockers?
– Drugs that block the action of the parasympathetic nervous system• Also called parasympatholytic
– Common use of anticholinergics is scopolamine transdermal patches • Treat or prevent sea-sickness by decreasing
gastric secretions and motility
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Cholinergic Blockers (cont’d.)• Anticholinergics are most commonly used
as preoperative medications – Atropine and glycopyrrolate (Robinul)
• Reduce secretions of the mouth, pharynx, bronchi, and GI tract and reduce gastric activity
– Used to prevent cholinergic effects during surgery, such as hypotension or bradycardia and some cardiac arrhythmias associated with general anesthetics or vagal stimulation
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