Term
Which postganglionic sympathetic neurons are not adrenergic |
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Definition
Those that release Dopamine and sympathetic innervation of the eccrine (thermoregulatory) sweat glands, which is cholinergic! |
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Term
Dopamine can act on what type of receptors |
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Definition
D1, D2 and alpha and Beta receptors |
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Term
What enzyme catalyzes the reactions of L-Dopa to dopamine |
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Definition
aromatic amino acid decarboxylase |
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Term
What enzyme catalyzes the reaction of NE to epinephrine |
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Definition
phenyl-N-methyl-transferase |
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Term
What enzyme catalyzes the step of dopamine to NE |
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Definition
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Term
Primary means of inactivation of catecholamines |
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Definition
Reuptake into nerve terminals |
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Term
Catechol-O-Methyl-Transferase (COMT) |
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Definition
is located extracellularly on membranes throughout the body. It can therefore metabolize released catecholamines into inactive metabolites. |
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Term
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Definition
Critical alpha-1 distribution is in the radial muscle of the iris, the vasculature, and the genitourinary (α-1a) and gastrointestinal sphincters. Activation of these receptors causes contraction of the muscle. |
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Term
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Definition
1. Also located in the vasculature, although they play a less critical role than the alpha-1. 2. Located on NE nerve terminals. So function as inhibitory autoreceptors. That is, activation of these receptors decreases the amount of NE released. 3. Located in the brainstem where activation leads to decreased sympathetic and increased parasympathetic nervous system activation. ** Points 2 and 3 are important for understanding why alpha-2 agonists are considered anti-adrenergic. |
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Term
Relative affinities of b2 for epi and NE |
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Definition
100 fold greater affinity for Epi |
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Term
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Definition
receptors are important because of their localization to cardiac muscle. 1. Activation leads to increased conduction and contractility in the heart. 2. Therefore, beta-1 receptor activation increases cardiac output. |
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Term
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Definition
Mediate vasodilation in skeletal muscle, bronchiodilation, and relaxation of bladder and uterine walls |
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Term
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Definition
Increase GFR, Sodium excretion and renal blood flow. causes vasodilation in renal, cardiac, cerebral, and mesenteric vasculature. |
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Term
What is the Main autonomic determinant of vascular tone/total peripheral resistance. |
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Definition
Alpha 1 activation which causes vasoconstriction |
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Term
Parasympathetic effects on total peripheral resistance |
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Definition
Parasympathetic nervous system activation will not alter total peripheral resistance, but direct-acting muscarinic agonists can. |
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Term
What effect does alpha1 activation have on intraocular pressure |
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Definition
decreases blood flow to ciliary body and trabecular network. Decreases production and increases outflow of aqueous humor. |
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Term
What effect does alpha 2 activation have on intraocular pressure |
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Definition
decreases production of aqueous humor and increases outflow of aqueous humor. |
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Term
What effect does beta 1 activation have on intraocular pressure |
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Definition
increases the production of aqueous humor |
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Term
What effect does beta 2 activation have on intraocular pressure |
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Definition
increases aqueous humor production and increases outflow of aqueous humor |
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Term
What effect does muscarinic activation have on intraocular pressure |
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Definition
causes contraction of ciliary muscle. Tension on trabecular network leads to increased outflow of aqueous humor through the network. |
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Term
What mediates sympathetic Regulation of the Bronchioles and what effects does it have |
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Definition
Beta-2 mediated. 1. Bronchodilation 2. Incresed cilial beat frequency 3. decreased vascular permeability 4. Inhibits release of inflammatory mediators from mast cells |
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Term
Effects of parasympathetic Regulation of the Bronchioles |
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Definition
Constricts bronchioles and increases mucous secretions |
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Term
Effects of sympathetic Regulation of the Urinary Bladder |
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Definition
Alpha 1a - Constricts sphincter and prostate as well as prostate capsule Beta 2 - Relaxtion of bladder wall (detrusor muscle) |
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Term
Parasympathetic Regulation of the Urinary Bladder |
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Definition
Muscarinic activation causes relaxation of sphincter and contraction of bladder wall |
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Term
What are the majority of cholinergic receptors in the CNS |
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Definition
95% Muscarinic, 5% Nicotinic Nueral |
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Term
What is the response to Cholinergic CNS stimulation |
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Definition
Mimics peripheral sympathetic effects, Increase blood pressure, heart rate, pupil dilation. Cognitive -- confusion, altered memory, coma. Motor -- Initial tremors followed by convulsion |
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Term
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Definition
Rapidly degraded <20 sec. Stimulates both nicotinic and muscarinc receptors. Clinically usefeul in settings where rapid stimulation/degradation is necessary i.e. cataract surgery. |
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Term
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Definition
(1) Synthetic carbamoyl choline ester. (2) Long acting-NOT hydrolyzed by ChEs (3) Only stimulates muscarinic |
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Term
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Definition
(1) synthetic carbamoyl choline ester (2) Long acting-NOT hydrolyzed by ChEs. (3) Stimulates BOTH muscarinic and nicotinic (4) causes release of ACh from synapses |
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Term
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Definition
(1) Recently (2000) approved (2) Selective for M3 receptors |
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Term
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Definition
(1) Plant alkaloid (2) only muscarinic |
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Term
ChE inhibitors act by what mechanism |
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Definition
ChE inhibitors, except the organophosphates, are competitive inhibitors of ChE. |
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Term
Edrophonium and Ambenonium |
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Definition
ChE inhibitors (1) Brief duration min (Edrophonium) to hrs (Ambenonium) (2) electrostatic forces and hydrogen bonding. (3) reversible |
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Term
Neostigmine, physostigmine, pyridostigmine |
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Definition
ChE inhibitors. Binding mechanism similar to ACh. Longer duration 0.5-6 hrs. |
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Term
Organophosphates—Isoflurophate and echothiophate |
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Definition
(1) phosphorylate active site of ChE forming a phosphoryl-enzyme complex (2) very slowly reverses (hundreds of hours). (3) With time bond strength increases -“ages”, and the phosphoryl- ChE link becomes essentially irreversible. (4) Need synthesis of new ChE. |
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Term
Which ChE inhibitors do not cross the BBB |
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Definition
Neostigmine, edrophonium, pyridostigmine, & ambenonium & Echothiophate |
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Term
Which ChE inhibitors do cross the BBB |
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Definition
Physostigmine, Isoflurophate, insecticides, & nerve gases |
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Term
Which drugs would be used to treat myasthenia gravis |
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Definition
Long-Term Oral Rx Is With ChE Inhibitors that Don’t cross the BBB: Neostigmine (short duration [2-4 hr]) Pyridostigmine (3-6 or 6-8 hr [sustained release]) Ambenonium (3-8 hr) |
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Term
Drugs used for treatment of Glaucoma |
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Definition
(1) topical (pilocarpine, carbachol) or (echothiophate, 2nd choice due to side effects) |
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Term
Drugs used to treat xerostomia (dry mouth) |
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Definition
(1) Pilocarpine- (2) Cevimeline- M3 selective, longer lasting, fewer side effects |
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Term
Treatment of choice for urinary bladder atony |
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Definition
Treatment-cholinomimetic or ChE Inhibitor (1) bethanecol- M3 selective (2) neostigmine- relatively short duration (2-4 hr) |
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Term
Neuromuscular blockade during surgery |
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Definition
Treatment- ChE Inhibitor of moderate duration (1) Neostigmine- increases ACh in neuromuscular junction to overcome competitive blockade |
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Term
treatment for Intoxication by Antimuscarinic Agents i.e. (1) Poisoning with atropine, antihistamines, tricyclic antidepressants |
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Definition
Physostigmine is the drug of choice (a) crosses the blood-brain barrier (b) reverse many of the central and peripheral effects of poisoning by atropine and related antimuscarinic agents. (c) can cause seizures. |
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Term
What are the four drugs used to treat alzeimers |
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Definition
Tacrine, Donepezil, Rivastigmine, Galantamine |
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Term
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Definition
Used to treat alzeimers disease (a) modest increase in cognitive function. (b) can cause reversible liver damage (30-50%) (c) Cholinergic side effects that they can also limit use. (d) no longer widely used in clinical practice. |
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Term
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Definition
produces modest improvement in some measures of cognitive function in patients with Alzheimer’s disease. (a) more selective to CNS ChE, less toxic (b) long duration of action – single dose/day is possible |
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Term
Rivastigmine and galantamine |
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Definition
Recently FDA approved to treat alzeimers. (b) Long-acting, but given twice daily (c) Pattern of toxicities is less severe, like donepezil, but still includes nausea, vomiting, diarrhea, and insomnia. (d) Efficacy similar to that of donepezil |
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Term
Three primary contraindications of cholinomimetics |
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Definition
Asthma, Coronary insufficiency and peptic ulcers. |
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Term
By what mechanism do antimuscarinics work? |
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Definition
Competitive antagonists at the muscarinic receptor. |
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Term
Prototypical antimuscarinic drugs |
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Definition
Atropine and scopolamine, atropine only crosses BBB at higher doses. |
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Term
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Definition
antimuscarinic. Like a short acting atropine used in opthalmic exams to help dilate pupil. Lasts about 6 hours |
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Term
What drug is used in conjunction with antimuscarinic during opthalmic exams to help dilate the pupil. What receptor does it act upon |
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Definition
Phenylephrine. Alpha-adrenergic agonist. |
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Term
What use do antimuscarinics have in presurgery patients |
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Definition
Stops the heart rate from decreasing too much. Not routine. Used in patients in danger of cardiac slowing i.e. downs syndrome patients |
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Term
What are antimuscarinics used for in post surgical patients |
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Definition
ChE inhibitors are sometimes used to help stop neuromuscular blockade after surgery by increasing ACh at nicotinic and muscarinic synapses. In this case Antimuscarinic drugs can be coadministered to prevent unwanted side effects of muscarinic activation |
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Term
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Definition
Used as a ChE reactivator from organophosphate poisoning. Must be applied within hours of poisoning |
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Term
Drug of choice for organophosphate poisoning |
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Definition
Atropine. Also given with Pralidoxime |
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Term
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Definition
Selective M3 antagonist. Used for urinary urgency/incontinence and bed wetting. Relaxes detrusor and tightens sphincter. |
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Term
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Definition
New drug, relatively selective for M3, used like Tolterodine but with less side effects (especially dry mouth)and a little more efficacy. |
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Term
Drug of choice for motion sickness and what side effects does it have |
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Definition
Scopolamine patch. Can cause dry mouth, drowsiness Rare serious CNS effectsdepression, amnesia, excitation, psychotic episodes |
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Term
Two drugs that can be used for Bronchospasms |
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Definition
Ipratropium: inhalant antimuscarinic, not very selective. Not absorbed well so it doesn't produce many side effects. Lasts 4-6 hrs longer if given with an Alpha 2 agonist Tiotropium: Like ipratropium but lasts longer 24 hr duration and is selective for M1 and M3 |
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Term
Treatment of Parkinsons disease |
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Definition
Usually levodopa or carbidopa but antimuscarinics were used prior to there development to decrease the cholinergic input and restore balance between excitatory and inhibitory signals. Still can be used in some populations to control tremors but mostly as a secondary treatment due to side effects. |
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Term
Antimuscarinic contraindications / precautions |
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Definition
Glaucoma Obstructive or paralytic GI disease Myasthenia gravis Antimuscarinics contraindicated in pathological conditions where blockade of PSNS or skeletal muscle system receptors would worsen symptoms. |
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Term
Treatment for antimuscarinic toxicity and symptoms. |
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Definition
Treat with ChE inhibitors(physostigmine), remove source, gastric lavage, diazepam is used to reduce CNS mediated convulsions. Symptoms: Blind as a bat, dry as a bone, red as a beet, hot as a hare, and mad as a hatter |
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Term
By what mechanism do organophosphates work |
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Definition
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Term
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Definition
Acetylcholine, Bethanechol, Carbachol, Cevimeline, Pilocarpine |
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Term
short acting AChesterase inhibitors |
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Definition
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Term
Longer acting ACh esterase inhibitors |
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Definition
Neostigmine, Physostigmine, Pyridostigmine, |
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Term
Irreversible ACh esterase inhibitors |
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Definition
Isoflurophate, Echothiophate |
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Term
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Definition
Tacrine(not used much), Donepezil, Rivastigmine, Galantamine, |
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Term
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Definition
Atropine, Scopolamine, Tropicamide, Tolterodine (used for urinary incontinence and bedwetting), Solifenacin and Oxybutynin (urinary incontinence), Ipratropium and Tiotroprium (Bronchospasms), Glycopyrrolate |
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Term
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Definition
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Term
The Alzheimers drugs act by what mechanism |
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Definition
They are ACh esterase inhibitors |
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