Pharmacology An Introduction: Chapter 7: Drugs Affecting The PNS

  1. Acetylcholinesterase
    An Enzyme That Inactivates Acetylcholine
  2. Anticholinergic
    Refers To Drugs or effects that reduce the activity of the parasympathetic nervous system
  3. Cholinergic
    Refers to the nerves and receptors of the parasympathetic nervous system; Also refers to the drugs that stimulate this system
  4. Muscarinic Receptor
    An Older But More Specific Term For the cholinergic receptor on smooth and cardiac muscle
  5. Nicotinic-Muscle (Nm) Receptor
    Cholinergic receptor located at the neuromuscular junction of skeletal muscle
  6. Nicotinic-Neural (Nn) Receptor
    Cholinergic receptor located on both sympathetic and parasympathetic ganglia
  7. Parasympatholytic
    Refers to Drugs (Anticholinergic) that decrease activity of the parasympathetic nervous system
  8. Parasympathomimetic
    Refers to drugs (Cholinergic) that mimic stimulation of the parasympathetic nervous system
  9. What is the neurotransmitter of the parasympathetic system
  10. What are the nerves that release ACH
    Cholinergic Nerves
  11. What Are receptors that respond to cholinergic stimulation
    cholinergic receptors
  12. What Are drugs that bind to cholinergic receptors and produce effects similar to ACH
    Cholinergic Drugs
  13. What is antagonism
    When drugs bind to receptor and do not produce an effect
  14. What Are cholinergic blocking drugs
    Drugs that bind to cholinergic receptors and don't produce an effect
  15. What change occurs when ACH is released and travels to smooth or cardiac muscle membrane
    Parasympathetic Stimulation
  16. What Enzyme is found in the cholinergic receptor
  17. What Is acetylcholinesterase
    A Enzyme that inactivates ACH only when it is outside a nerve ending and not on the receptor
  18. Why do the effects of ACH las only a few seconds
    Inactivation of ACH occurs so quickly
  19. What does the cholinergic nerve ending look like
    Image Upload 1
  20. How does the transfer of Acetylcholine work in a nutshell
    Presynaptic nerve releases ACH, Postsynaptic membrane contains the cholinergic receptor, Acetylcholinesterase inactivates ACH
  21. What is the neurotransmitter for all 3 cholinergic receptors
  22. What Class of Cholinergic blocker is required to block all effects of ACH
    All 3 of them
  23. What Are The Three cholinergic receptors
    • Muscarinic receptor
    • Nn Receptor
    • Nm Receptor
  24. Muscarinic Receptor
    Receptors at the parasympathetic postganglionic Nerve endings
  25. What Is he term Muscarinic from
    The drug muscarine
  26. What is the drug Muscarinic
    An alkaloid obtained from a particular mushroom, One of first drugs used to function on ANS, produces effects similar to ACH but only at muscarinic receptor sites
  27. What Are drugs that act like ACH or muscarine
    Cholinergic, or muscarinic drugs
  28. What are drugs that block ACH
    Anticholinergic or antimuscarinic drugs
  29. What is Nn
  30. What are the Nn Receptors
    Cholinergic receptors at the ganglionic sites of both sympathetic and parasympathetic nerves
  31. What is the term Nicotinic derived from
    The drug nicotine, the alkaloid obtained from the tobacco plant
  32. Why did early pharmacologists use nicotine to study the ANS
    It Stimulates the Autonomic Ganglia in low doses and blocks the autonomic ganglia in high doses
  33. What are ganglionic stimulants
    Drugs that act like ACH in low doses of nicotine
  34. What are ganglionic blockers
    Drugs that block ACH or act like high doses of nicotine
  35. What is Nm
  36. What is the Nicotinic-Muscle Receptor
    The cholinergic receptor at the NMJ or skeletal muscle
  37. What is NMJ
    Neuromuscular Junction
  38. What act like ACH at the Neuromuscular junction
  39. What are Neuromuscular Blockers
    Drugs that Block the effects of ACH at the NMJ
  40. What are skeletal muscle relaxants
    Drugs that Block the effects of ACH at the NMJ
  41. What Are Cholinergic Drugs
    Drugs that mimic the actions of ACH at the Muscarinic receptors
  42. What Is another term Similar to cholinergic drugs
    Parasympathomimetic drugs
  43. What are the two groups cholinergic drugs are divided into
    • Direct-Acting
    • Indirect-Acting
  44. What are the direct-drugs
    Drugs that bind to the muscarinic receptors and produce effects similar to those of ACH
  45. What Are Indirect-Acting Drugs
    Drugs that inhibit the enzyme Acetylcholinesterase
  46. What Happens when you inhibit the enzyme acetylcholinesterase
    It Allows ACH to accumulate at each of the cholinergic receptor sites so a greater number of receptors become stimulated and the ACH effects are prolonged
  47. Where do direct-acting cholinergic drugs bind
    Muscarinic receptors
  48. Why Is ACH not useful as a drug
    Extremely short duration of action
  49. What Are the derivatives of ACH
    • Methacholine
    • Bethanechol
  50. Why were the derivatives of ACH synthasized
    To produce effects like ACH but more slowly inactivated by Acetylcholinesterase so the DOA is much longer
  51. What are the main pharmacological effects of ACH
    • Increase in GI secretions
    • Motility
    • Increase in Genitourinary activity
    • Bronchoconstriction
    • Miosis
    • Vasodilation
    • Decrease in heart beat
  52. What does vasodilation cause
    Decrease in BP
  53. What are the alkaloids of ACH
    • Muscarine
    • Pilocarpine
  54. What has no clinical importance except in cases of accidental poising
  55. What Is used in the form of eyedrops for treatment of Glaucoma that is a alkaloid that acts like ACH
  56. What is Bethanechol used for
    It is one of the few ACH drugs that are not short acting. It is administered orally to stimulate the urinary and intestinal tracts. Because of general anesthetics, elderly or other conditions they may have bowel or bladder retention
  57. What does overstimulation by Bethanechol cause
    Urinary frequency and diarrhea
  58. Why are cholinergic drugs used locally
    During Ophthalmic examination (To Constrict the pupil) and in treatment of Glaucoma
  59. What does glaucoma do
    Glaucoma will cause blindness by gradually destroying the retina which causes blindness
  60. how will Cholinergic drugs help glaucoma
    Will produce miosis which promotes better drainage of intraocular fluid and this lowers pressure
  61. What are indirect-acting cholinergic drugs known as
    The anticholinesterases
  62. What do Direct-acting cholinergic drugs do
    Inhibit the enzyme acetylcholinesterase and allow accumulation of ACH at all cholinergic receptor sites
  63. What are anticholinesterase drugs subdivided into
    • Reversible inhibitors
    • Irreversible inhibitors
  64. What is the main use of acetylcholine
    Miotic in cataract surgery
  65. What does Bethanechol for
    Nonobstructive urinary retention
  66. What does carbachol for
    Treatment of glaucoma
  67. What is Pilocarpine for
    Treatment of glaucoma
  68. What is Ambenonium for
    Treatment of myasthenia gravis
  69. What is demacarium for
    Treatment of glaucoma
  70. What is edroponium for
    Diagnosis of myasthenia gravis, antidote for curare-type drugs
  71. What is galantamine for
    Treatment of Alzheimer's disease
  72. What is Neostigmine for
    Treatment of myasthenia gravis, antidote for curare-type drugs
  73. What is Physostigmine for
    Antidote to Anticholinergic drugs, treatment of glaucoma
  74. What are pyridostigmine for
    Treatment of myasthenia gravis, antidote for curare-type drugs
  75. What is tacrine for
    Treatment of alzheimer's disease
  76. What is donepezil for
    Treatment of alzheimer's disease
  77. What are reversible inhibitors used for
    diagnosis and treatment of myasthenia gravis, and as antidotes to reverse the effects that block cholinergic and Nicotinic receptors
  78. What is myasthenia gravis
    It affects the skeletal muscle, it is characterized by insufficient Acetylcholine activity
  79. What is the duration of neostigmine
    2-4 hours
  80. What Is the duration of pyridostigmine
    3-6 hours
  81. What is the duration of ambenonium
    4-8 hours
  82. Neostigmine, pyridostigmine, and Ambenonium are administered orally for what treatment
    Treatment of myasthenia gravis
  83. Neostigmine, pyridostigmine, and Ambenonium are administered IV for what
    Reverse the effects of excessive cholinergic blockade
  84. What are Quaternary amines
    Charged compounds, they do not cross the blood-brain barrier and produce affects only at peripheral receptor sites. Examples are Neostigmine, pyridostigmine, and ambenonium
  85. What is Physostigmine
    Not a charged compound, and does not produce effects on the brain. Used parenterally to revers the CNS effects of excessive Anticholinergic blockade and as eyedrops in the treatment of Glaucoma
  86. What are the irreversible inhibitors of acetylcholinesterase
    Derivatives of organophosphate compounds widely used as insecticides, pesticides, and as chemical warfare agents. Have extremely long durations of action because they form irreversible bonds with the acetylcholinesterase enzyme
  87. What is echothiophate used for
    In very small doses usually used as eye drops of glaucoma, in larger doses these drugs produce severe toxicity.
  88. What is cholinergic crisis
    Caused by large dose of echothiophate it can quickly cause respiratory paralysis and death
  89. What is the most common adverse effects of cholinergic drugs
    Nausea, vomiting, diarrhea, blurred vision, excessive sweating, muscular tremors, bronchoconstriction, bradycardia, and hypotension.
  90. What happens in toxic overdose of cholinergic drugs
    Muscular paralysis and respiratory depression that may cause death
  91. What is the main antidote for cholinergic drugs
    Administration of Anticholinergic drugs, such as atropine, which compete with ACH for the muscarinic receptor and reverse the effects
  92. What is Cholinergic crisis
    Term used to describe the effects of excessive drug dosage in patients with myasthenia gravis
  93. What does ACH cause at high concentrations
    Excessive stimulation of muscarinic receptors, but blockade of nicotinic receptors. This causes respiratory paralysis because respiratory muscles are voluntary in nature
  94. In ACH overdose what can be used to bring the acetylcholinesterase levels to normal
    Atropine or pralidoxime
  95. What can farmers that spray there fields with Derivatives of anticholinesterase experience
    Cholinergic crisis, unless masks or enclosed tractor cabs are used
  96. What does pralidoxime do
    A drug that can reactivate the acetylcholinesterase enzyme after it has been inhibited by an irreversible inhibitor, most effective immediately after exposure. Also the antidote to organosphate chemical warfare agents.
  97. What are anticholinesterase drugs used for
    Treatment of Glaucoma, myasthenia,gravis, urinary retention, intestinal paralysis, alzheimer's disease, and as antidotes to the curaretype skeletal blockers and the Anticholinergic drug
  98. What is myasthenis gravis believed to be due to
    An Autoimmune reaction where the body produces antibodies that attack the Nm receptor, thus you loose muscle tone and strength
  99. What is used to increase the ACH levels for myasthenis gravis
    Pyridostigmine and ambenonium
  100. What is another name for urinary retention
    Atony of the bladder
  101. What is another name for Intestinal Stasis
    Paralytic ileus
  102. What are Urinary retention and Paralytic ileus usually treated by
    Neostigmine, it increases level of ACH to stimulate bladder contraction and intestinal peristalsis
  103. What is Alzheimer disease
    A degenerative brain condition that occurs in some individuals with advanced age. A loss of neuronal synapses and a reduction of ACH levels in the brain, which cause memory loss, dementia, and general deterioration of mental function
  104. What drugs are used to help treat alzheimer's disease
    • Two reversible anticholinesterase drugs:
    • Tacrine
    • Donepezil
    • They both increase activity in the brain, the effects are more notable in the beginning and lessen as the disease progresses. Lecithin is a precursor of ACH and is usually administered to further increase ACH levels
  105. What are skeletal muscle blockers used for
    In surgery to produce paralysis of skeletal muscle, at high doses it may cause respiratory paralysis
  106. What do you do if you administer too much skeletal muscle blockers
    If that does happen administer neostigmine to increase ACY and antagonize the action of the skeletal muscle blockers
  107. What do Anticholinergic drugs do
    Block the cholinergic receptors and produce effects similar to decreasing the activity of the parasympathetic system. This includes urinary and intestinal inhibition, cardiac stimulation, and central effects in the brain of stimulant and depressant effects
  108. What is the antidote for anticholinergic drugs
    Usually physostigmine, because it can pass the blood-brain barrier, the increase ACH produced compete with the anticholinergic drugs for the receptor
  109. What are anticholinergic drugs
    Cholinergic blocking drugs that bind to the muscarinic receptors, they act by competitive antagonism of ACH
  110. What are the oldest anticholinergic drugs
    atropine and scopolomine
  111. Where were Atropine and Scopolamine obtained from
    The Belladonna Plant and are usually called Belladonna alkaloids
  112. What is the Vagus nerve
    The Parasympathetic nerve of the hear
  113. What is used to increase heart rate
    anticholinergic drugs, they decrease the activity of the vagus nerve thus hear rate increases
  114. What drug is administered pre-op to inhibit secretion that may interfere with general anesthetics
    Anticholinergic drugs, ACH increases the secretions and anticholinergic drugs produce brochodilation and so can also be used in asthma
  115. What do anticholinergic drugs do to the GI system
    Reduce salivary and GI secretions so don't administer if intestinal obstruction. They are used as antispasmodics in GI disorders such as irritable bowel syndrome or peptic ulcers
  116. What do anticholinergic drugs do to the genitourinary system
    Inhibit urinary peristalsis and the voiding of urine. May be used on people suffering from enuresis. Contraindicated in males with hypertrophy of the prostate gland.
  117. What do most anticholinergic drugs that gain access to the brain do
    Give a depressant effect. usually drowsiness and sedation, can be used as sleep aids
  118. What will Scopolamine do
    In little amounts it Act as a sleep aid, in larges doses there can be a mixture of both CNS stimulant and depressent
  119. What will both atropine and scopolamin produce at toxic doses
    Produce excitation, delirium, hallucinations, and profound CNS depression that can lead to respiratory arrest and death
  120. What are anticholinergic actions useful for
    Parkinson's disease and as antiemetics for motion sickness
  121. What is the Main use and common dosage of Atropine
    • To increase heart rate, preop medication, enuresis, GI and Biliary colic, antidote to cholinergic drugs Mydriatic and Cycloplegic
    • .4-.6 mg PO,IV,IM,SC Topical Eyedrops
  122. What is the Main use and common dosage of Hyoscyamine
    • Same as Atropine
    • .25-1.0 mg PO, IV
  123. What is the Main use and common dosage of Scopolamine
    • Motion sickness
    • 1 Patch every 3 days
  124. What is the Main use and common dosage of Homatropine
    • Mydriatic
    • Ophthalmic Solution
  125. What is the Main use and common dosage of Dicylomine
    • Treatment of GI disorders such as ulcers, colitis
    • 80-160 mg PO
  126. What is the Main use and common dosage of Glycopyrrolate
    • Treatment of ulcers
    • 2-6mg PO
  127. What is the Main use and common dosage of methscopolamine
    • Treatment of GI disorders such as ulcers, colitis
    • 2.5-10 mg PO
  128. What is the Main use and common dosage of Oxybutynin
    • Treatment of overactive bladder
    • 5-15 mg PO
  129. What is the Main use and common dosage of propantheline
    • Treatment of GI disorders such as ulcers, colitis
    • 22.5-60mg PO
  130. What is the Main use and common dosage of tolterodine
    • Treatment of overactive bladder
    • 2-4 mg PO
  131. What is cycloplegia
    loss of accommodation
  132. What are the drugs used in ophthalmology to facilitate examination of the retina or lens
    Anticholinergic drugs
  133. What type of drug should not be given to a patient with glaucoma
    Anticholinergic because it will increase pupillary dilation and closure of the drainage pathway
  134. What is the most frequent adverse effect of anticholinergic
    Caused by excessive blockade of the PNS, symptoms include, dry mouth, visual disturbances, urinary retention, constipation, flushing and dryness of skin, fever, tachycardia, symptoms of both CNS stimulation and depression
  135. What are the effect on the skin from anticholinergic drugs caused by
    Anticholinergic effect that inhibit sweating mechanism and the vasodilate certain blood vessels causing flushing
  136. What happens to children who mistakenly eat the Belladonna berries
    Fever, tachycardia, dryness, mydriasis and flushing of skin in severe cases respiratory paralysis, coma, and death may occur withing hours
  137. What is treatment for overdose of belladonna
    Induce emesis or performing gastric lavage to limit absorption. Can use activated charcoal and saline cathartics are used to inactivate the drug. Physostigmine given IV antagonizes the action and useful if delirium and coma are present
Card Set
Pharmacology An Introduction: Chapter 7: Drugs Affecting The PNS
Cards for Pharmacology Navy C School