Cholinergic Drugs Flashcards
What type of Cholinergic Receptors predominate in the Heart?
M2
What type of Cholinergic Receptors predominate basically everywhere besides the Heart?
M3
What type of G Protein do M2 Receptors use?
M2 Receptors use Gi Proteins
What type of G Protein do M3 Receptors use?
M3 Receptors use Gq Proteins
Acetylcholine
Direct Acting, Non-Selective Cholinergic Agonist
Bethanechol
Direct-Acting, Selective mAChR Agonist
Carbachol
Direct-Acting, Non-Selective Cholinergic Agonist
Cevimeline
Direct-Acting, Non-Selective Cholinergic Agonist
Methacholine
Direct-Acting, Selective mAChR Agonist
Pilocarpine
Direct-Acting, Selective mAChR Agonist
Varenicline
Direct-Acting, Selective nAChR Agonist
Ambenomium
Quaternary (Charged), Indirect-Acting Cholinergic Agonist
AChE Inhibitor
Edrophonium
Quaternary (Charged), Indirect-Acting Cholinergic Agonist
AChE Inhibitor
Pyridostigmine
Quaternary (Charged), Indirect-Acting Cholinergic Agonist
AChE Inhibitor
Echothiophate
Quaternary (Charged), Indirect-Acting Cholinergic Agonist
AChE Inhibitor
Neostigmine
Quaternary (Charged), Indirect-Acting Cholinergic Agonist
AChE Inhibitor
Physostigmine
Tertiary (Neutral), Indirect-Acting Cholinergic Agonist
AChE Inhibitor
Donepezil
Tertiary (Neutral), Indirect-Acting Cholinergic Agonist
AChE Inhibitor
Galantamine
Tertiary (Neutral), Indirect-Acting Cholinergic Agonist
AChE Inhibitor
Rivastigmine
Tertiary (Neutral), Indirect-Acting Cholinergic Agonist
AChE Inhibitor
Tacrine
Tertiary (Neutral), Indirect-Acting Cholinergic Agonist
AChE Inhibitor
Do Tertiary or Quaternary AChE Inhibitors have the capability of crossing the BBB? How Come?
Tertiary AChE Inhibitors (Donepezil, Rivastigmine, Galantamine, Physostigmine, and Tacrine) are Neutral (Uncharged) and thus are lipid soluble and can cross the BBB
What are the Quaternary (Charged/Polar) AChE Inhibitors?
Ambenomium, Pyridostigmine, Echothiophate, Edrophonium, Neostigmine
What are the Tertiary (Uncharged/Neutral) AChE Inhibitors?
Donepezil, Rivastigmine, Galantamine, Physostigmine, Tacrine
What Cholinergic Agonist might you use to treat Glaucoma?
Carbachol or Pilocarpine
They are Cholinergic Agonists (Non-Selective and mAChR Selective respectively) and will act on M3 receptors in the eye to stimulate an increase in the outflow of Aqueous Humor, decreasing Intraocular pressure
What Cholinergic Agonist might you use to treat GI/GU issues, including, but not limited to, Heartburn and Urinary retention.
Bethanechol
This Selective mAChR Agonist could be used to treat such GI/GU issues
What mnemonic may be used to remember the symptoms of muscarinic stimulant toxicity? What does it stand for?
DUMMBBELS
Diarrhea, Urination, Miosis, Muscle weakness, Bradycardia, Bronchospasm, Emesis, Lacrimation, Sweating/Salivation/Seizures
What Cholinergic Agonist might you use to treat Myasthenia Gravis?
Pyridostigmine or Neostigmine
What Cholinergic Agonists might you use in order to reverse the Neuromuscular Blockade of Anesthesia?
Neostigmine or Edrophonium
What Neurological Conditions may benefit from treatment with AChE Inhibitors?
Parkinson’s
Alzheimer’s
Dementia
What AChE Inhibitor is best preferred in order to treat OD via Anti-Cholinergic drugs/compounds?
Physostigmine
What Drug interaction of AChE Inhibitors must you try to avoid when dealing with a Neuromuscular blockade for anesthesia?
Succinylcholine. AChE Inhibitors will interact with Succinylcholine to Agonist the Phase I block and antagonize the Phase II block
What is the recommended treatment for Cholinergic Poisoning (i.e. Toxicity due to too high of Cholinergic activity)?
Atropine
What is the recommended therapy for Organophosphate poisoning resulting in Cholinergic Toxicity?
Pralidoxime (an AChE Regenerator) Atropine (a mAChR Selective Antagonist) A Benzodiazepine (an anticonvulsant)
Pralidoxime
Pralidoxime is an AChE Regenerator capable of removing an Organophosphate from AChE if administered within a sufficient timeframe
Atropine
Reversible, Tertiary (Neutral), mAChR Selective Antagonist
What mAChR Antagonist would you choose to use in order to treat motion-sickness or sea-sickness? What are some possible side effects of this drug?
Scopolamine is classically known for being used to treat motion-sickness or sea-sickness.
Scopolamine side effects may include Amnesia and Drowsiness
What mAChR Antagonists might you use in the management of Pt’s with COPD?
Ipratropium or Tiotropium, inhaled mAChR Antagonists, may be used to facilitate improved breathing and exercise tolerance in Pt’s with COPD by inducing Bronchodilation and decreased secretions
What mAChR Antagonists might you use to relieve bladder spasms following Urologic Surgery and/or involuntary voiding in Pt’s with Neurological diseases?
Oxybutynin - a somewhat M# Selective MAChR Antagonist
Trospium - a Nonselective, mAChR Antagonist with similar efficacy to Oxybutinin
Darifenacin, Solifenacin, and Tolterodine - all 3 are M3 Selective mAChR Antagonist that are advantageous due to their longer half-life and decreased incidence of symptoms (constipation, xerostomia)
What mAChR Antagonists might you use to help reduce the Tremors and Rigidity in Pt’s with Parkinson’s Disease?
Benztropine and Trihexyphenidyl may be used to hep reduce the tremors and rigidity in Pt’s with Parkinson’s
What general GI symptoms might you expect when taking a mAChR Antagonist?
Prolonged GI emptying and transit time
Decreased salivation > decreased gastric secretions
No real change in Intestinal or Pancreatic secretions
What condition might a Child get if they take a normal Adult dose of a mAChR Antagonist Drug?
“Atropine Fever”
mAChR Antagonist-induced Hyperthermia
What are the possible routes of administration for Scopolamine?
Injection
PO
Transdermal Patch
What Long-Acting mAChR Antagonist would you use in order to prevent the formation of Synechia (where the Iris of the eye fuses to the Cornea or the Lens) in Pt’s suffering from Uveitis or Iritis?
Homatropine
Between Ipratropium and Tiotropium, which of the two is a Longer-Acting, Inhalational mAChR Antagonist that only has to be used ONCE daily to help reduce COPD symptoms?
Tiotropium is longer-acting than Ipratropium and must only be used once daily
What is the first drug of choice when treating Bradycardia in the setting of Advanced Cardiac Life Support?
Atropine
When using Oxybutynin for relief of GU disorders including Urinary Frequency, Involuntary Voiding, etc., what side effects could an individual expect to experience?
Dry Mouth, Dizziness, Constipation, Blurred Vision, Dry Eyes, UTI
Trospium
A Non-Selective mAChR Antagonist that may be used to treat GU issues relating to Urinary Frequency. It’s similar in efficacy to Oxybutynin
Darifenacin
Darifenacin is a M3 Selective mAChR Antagonist that is useful in treating GU issues relating to Urinary frequency. Alongside, Solifenacin and Tolterodine, it offers less side effects than Oxybutynin or Trospium
Solifenacin
Solifenacin is a M3 Selective mAChR Antagonist that is useful in treating GU issues relating to Urinary frequency. Alongside Darifenacin and Tolterodine, it offers less side effects than Oxybutynin or Trospium
Tolterodine
Tolterodine is a M3 Selective mAChR Antagonist that is useful in treating GU issues relating to Urinary frequency. Alongside, Solifenacin and Darifenacin, it offers less side effects than Oxybutynin or Trospium
Oxybutynin
Oxybutynin is a somewhat M3 Selective mAChR Antagonist used in the treatment of GU issues relating to urinary frequency. Although Solifenacin, Darifenacin, and Tolterodine are more advantageous treatments as they come with decreased incidences of Oxybutynin’s side-effects of xerostomia and constipation
Where in the body is Pralidoxime Capable of regenerating AChE?
Pralidoxime is charged and thus only capable of regenerating AChE at the Neuromuscular Junction
Pirenzepine
Pirenzepine is a M1 Selective mAChR Antagonist that may be used to treat Peptic Ulcer Disease (BUT it is not approved in the US due to adverse effects). It works by inhibiting gastric secretions by Antagonizing M1 Receptors at their ganglion
Mecamylamine
Mecamylamine is a Synthetic, Tertiary Amine, Ganglion-Blocking Drug that competitively blocks the action of ACh at nAChR’s of both sympathetic and parasympathetic Ganglion (Blocking all Autonomic Outflow).
It may be used to improve Gi Absorption. It is approved to treat HTN and may be helpful in smoking cessation
What are the overall Organ System effects one might expect to see with a Ganglion-Blocking drug (such as Mecamylamine)?
A Ganglion-Blocking Drug (such as Mecamylamine) will induce organ system effects similar to Sympathetic effects, as they function to reduce Parasympathetic effects more throughout the body
If a patient presents with Muscle Fasciculations, what type of receptor MUST be involved?
AChR’s must be involved, as the only way you’ll get Muscle Fasciculations is if nAChR’s are being activated
