ANS Drugs Flashcards
Examples of sympathetic agonists
Dopamine
Isoproterenol
Sympathetic agonist
Sympathomimetic or adrenergic agonist.
Stimulate the sympathetic nervous system.
Directly activates specific adrenergic receptors.
Can increase release of norep from nerve terminals.
Primarily for effects on Ht, bronchial tree, nasal passage
Sympthatic Blockers
Inhibit sympathetic division
Prevent s/s with SNS active
Receptors divided into alpha and beta types
Drug effects depend on which receptor is activated
actions: slow HR, lower BP
Examples of Sympathetic Blockers
Propanolol
Regitine
Cardura
Cholinergic Agonists
Parasympathetic stimulator
Includes rest and digest response
2 subclasses: Direct and Indirect acting
Anti-cholinergic
Blocks effects of acetylcholine at muscarinic receptor.
Use has declined due to numerous s/e.
Used to dry secretions, tx asthma, prevent motion sickness.
Occasionally prescribed to accelerate HR, dry secretions, dilate the bronchi, dilate the pupil, Parkinson’s, IBS
Impact of agonist on Alpha 1
controls topical superficial bleeding
treats nasal congestion
delays absorption of local anesthetics
Impact of agonist on Alpha 2
Treats glaucoma
Treats HTN, decreases amount of norep
Reduction of redness, swelling of eyelid
Blocking of Alpha 1
Prevents norep from binding to receptor site.
Blocks postsynaptic receptor site -> decrease in vascular tone and increase vasodilation
Blocking of Alpha 2
increases adrenergic neurotransmitters
induces insulin secretion
decreases blood sugar levels
increase HR, arterial pressure
Impact of Beta 1 agonist
stimulate HR
Tx Ht Failure
Cardiac arrest
Shock
Impact of Beta 2 agonist
Produce bronchodilation
Delay preterm labor
Action of Isoproterenol (Isuprel)
stimulation of beta adrenergic receptor
increase HR, BP, conductivity, contractility;
bronchodilation
increased blood flow to skeletal muscles, splanchnic bed
relaxation of uterus
S/E of Atropine
drowsiness, blurred vision, tachycardia, dry mouth, urinary hesitancy, tachypnea, pulmonary edema, flushing, decreased sweating, predisposition to heat prostration, mydriasis, cycloplegia, photophobia, palp, tachycard, altered taste perception.
Adverse effects of Phentolamine
Hypotension, orthostatic hypotension, angina, MI, CVA
Arrhythmia, weakness, dizziness
What meds will treat non obstructive urinary retention
Doxazosin (Cardura)
What family of drugs treats myasthenia gravis
Acetylcholinesterase inhibitors
ie: Pyridostigmine
What is the ADR/interactions with other meds associated with Aricept
bradycardia, hypotension, increase GI secretion and activity, increased bladder tone, relaxation of GI and genitourinary sphincters, bronchoconstriction, pupil constriction.
Drug - drug interactions: NSAIDS - leads to anemia
When would Inderal not be given
If patient has diabetes or hepatic dysfunction
How would you reverse cholinergic reaction
By giving an anticholinesterase inhibitor such as Pralidoximine
Impact of too much anticholinesterase on the body
Muscle paralysis and weakness; Respiratory paralysis
Older adults have greater number of ADR - why?
Because their liver function and kidney function have decreased therefore, the liver cannot metabolize as well, kidney cannot excrete as well. GI problems decrease absorption rate.
What type of meds are preferred use post MI and post CHF
Beta adrenergic blocking agents such as Propranolol, Atenolol
How do Alpha 1 blocking agents impact BPH
By decreasing vascular tone, increasing vasodilation, and inhibiting the constricting of the urinary bladder
How/where does the body make acetylcholine and norepinephrine
Norep is made from tyrosine in the adrenal medulla.
Acetylcholine is made in the mitochondria from the components of choline and acetyl CoA.
When/where are acetylcholine and norep released
the neurotransmitters are released in the synaptic cleft between 2 neurons. they are released when the Ca+ gate at the end of the axon is opened and an influx of Ca+ triggers the release of neurotransmitters into the synaptic cleft.
How do neurotransmitters work
When they are released into the synaptic cleft, they travel across to the next neuron and attach to the receptor sites to trigger the next impulse. Norep released by postganglionic neuron and attaches to alpha and beta receptors. Acetylcholine released by presynaptic and postsynaptic ganglia and attaches to muscarinic and nicotinic receptors.
Know the difference between nicotinic and muscarinic receptors
Both are parasympathetic receptors; both receive cholinergic neurotransmitter, acetylcholine;
muscarinic receptors are in the visceral organs
nicotinic receptors are for muscle contraction
