Cholingergics Flashcards
- Cimetidine (OAT)
- Proadifen (OCT)
- Probenecid
- Drug metabolism inhibitor
- Decrease metabolism by direct enzyme inhibitor
- Common site of drug-drug interaction
- Increase circulating drug level
- Ethanol
- Phenobarbital
- Drug metabolism activators
- Increase metabolism by enhanced synthesis, reduced degradation, and direct enzyme action
- Increase toxicity
- Decrease circulating drug level
Bethanechol
- Cholinergic agonist – synthetic choline ester
- M receptors– CH3 and NH2 groups – para activation – especially GI tract
- Para hyperactivity
- Stimulate smooth muscle post-operatively – increased GI motility, sphincters relax, stimulate secretions
Carbachol
- Cholinergic agonist – synthetic choline ester
- M receptors –NH2 is poor substrate for AchE (prolongs drug action) - para activation
- Para hyperactivity
- Wide-angle glaucoma (constrict ciliary muscle)
Methacholine
- Cholinergic agonist – synthetic choline ester
- M receptors – CH3 group decreases interaction with N receptors - para activation
- Para hyperactivity
- Slow heart in severe tachycardia`
Pilocarpine
*Cholinergic agonist – natural alkaloid
*M receptor selective -
Para activation - sweat and salivary glands (increase secretions)
*Para hyperactivity
*Glaucoma (short term treatment of acute angle-closure), treat dry mouth
Ambenonium
- Competitive cholinesterase inhibitor - carbamate
- Reversible – short acting- indirect para activation (keeping ACh in synapse)
- Paralysis, respiratory failure, sweating, GI cramps, salivation, miosis, tearing
- Myasthenia gravis
Edrophonium
- Competitive cholinesterase inhibitor - simple alcohol with quartenary ammonium
- Reversible – short acting- indirect para activation (keeping ACh in synapse)
- Paralysis, respiratory failure, sweating, GI cramps, salivation, miosis, tearing
- Paralysis, respiratory failure, sweating, GI cramps, salivation, miosis, tearing
- Myasthenia gravis, ileus, arrhythmias, reversal of neuromuscular blockade (short)
Neostigmine
*Competitive cholinesterase inhibitor – carbamate with quartenary ammonium
*Reversible – short acting
indirect para activation (keeping ACh in synapse)
*Paralysis, respiratory failure, sweating, GI cramps, salivation, miosis, tearing
*Myasthenia gravis, ileus, arrhythmias, reversal of neuromuscular blockade (Long)
Physostigmine
*Competitive cholinesterase inhibitor – carbamate with tertiary amine
*Reversible – short acting
indirect para activation (keeping ACh in synapse)
*Paralysis, respiratory failure, sweating, GI cramps, salivation, miosis, tearing
*Paralysis, respiratory failure, sweating, GI cramps, salivation, miosis, tearing
*Myasthenia gravis
- Diisopropyl-fluorophosphate
- Echothiopate
- Carbaryl
- Malathion
- Parathion
- Tetraethyl-pyrophosphate
*Noncompetitive cholinesterase inhibitor – OP insecticie
*Reacts more with PChE – irreverislbe – long acting, very toxic - indirect para activation (keeping ACh in synapse)
*Paralysis, respiratory failure, sweating, intestinal cramps, salivation, miosis, tearing
*Echothiopate for glaucoma
Malathion for head lice
- Sarin
- Soman
- Noncompetitive cholinesterase inhibitor – nerve gas
- Reacts more with PChE – irreverislbe – long acting, very toxic - indirect para activation (keeping ACh in synapse)
- Paralysis, respiratory failure, sweating, GI cramps, salivation, miosis, tearing
Pralidoxime
- AchE reactivator – cholinesterase inhibitor
- Reactivates AChE (must occur before AChE aging)
- Little CNS effects
- Step 2 following OP intoxication
Atropine
*Cholinergic antagonist – highly muscarinic selective (low potency at nicotinic), no M subtype selectivity – 3 amine
*Quickly distributed in CNS 30-60 minutes – salivary, bronchial, and sweat glands are most sensitive
Parasympathetic inhibition - long-acting eye effects (mydriasis and cycloplegia), decreases gastric secretions, therapeutic doses only mild vagal stimulation
*Increased body temperature due to impaired ability to sweat (atropine fever), hallucinations, amnesia, sedation, excitement, dry mouth
*OP and cholinergic agonist toxicity, elicit tachycardia following brady from MI, anti-parkinson, relieves urinary incontinence, mydriasis (7-10 days), anti-motion sickness
Homatropine
- Cholinergic antagonist – muscarinic selective - 3 amine
- Parasympathetic inhibition - intermediate length eye effects (mydriasis and cycloplegia)
- Hallucinations, amnesia, sedation, excitement, dry mouth
- Mostly used for eye effects (topical agent) – mydriasis (1-3 days)
Scopolamine
*Cholinergic antagonist – very muscarinic selective – 3 amine
*Quickly distributed after administration, primarily central effects
Parasympathetic inhibition - short acting eye effects (mydriasis and cycloplegia)
*Sedation and dry mouth, hallucinations, amnesia, sedation, excitement
*Anti-motion sickness, amnesia (pre-anesthetic), mydriasis (3-7 days), induction of amnesia
Methscopolamine
- Cholinergic antagonist – muscarinic selective – 4 ammonium
- PNS activity only - parasympathetic inhibition
- Dry mouth, tachycardia, red skin, excess mydriasis, cycloplegia, dry eyes, urinary retention
- Mostly GI diseases
Trihexyphenidyl
- Cholinergic antagonist – muscarinic selective – 3 amine
- Parasympathetic inhibition
- Hallucinations, amnesia, sedation, excitement
- Decrease uncoordinated movement and excess salivation for parkinsons
Tropicamide
- Cholinergic antagonist – muscarinic selective – 3 amine
- Parasympathetic inhibition - very short acting eye effects (mydriasis and cycloplegia)
- Hallucinations, amnesia, sedation, excitement
- Mostly used as topical ocular treatment – mydriasis (6 hours)
Cyclopentolate
- Cholinergic antagonist – muscarinic selective
- Parasympathetic inhibition
- Dry mouth, tachycardia, red skin, excess mydriasis, cycloplegia, dry eyes, urinary retention
- Mydriasis – 1 day
Ipratropium
- Cholinergic antagonist – muscarinic selective – 4 ammonium
- Parasympathetic inhibition – bronchodilation, tachycardia, decreased salivation
- Dry mouth, tachycardia, red skin, excess mydriasis, cycloplegia, dry eyes, urinary retention
- Topical - minimizes mucociliary clearance issues (pts with airway problems – COPD)
Tiotropium
- Cholinergic antagonist – muscarinic selective
- Parasympathetic inhibition – longer acting
- Dry mouth, tachycardia, red skin, excess mydriasis, cycloplegia, dry eyes, urinary retention
- Topical - targets bronchodilation and minimizes mucociliary clearance issues
- Darifenacin
- Solifenacin
- Tolterodine
- Cholinergic antagonist – M3 selective
- Parasympathetic inhibition – longer acting relaxation of smooth muscle in GU system
- Excessive urinary retention
- Urinary urgency, bladder spasms
Mecamylamine
*Cholinergic antagonist – nicotinic selective – 2 amine – nondepolarizing competitive antagonists
*Inhibit neurotransmission by N1 receptors in both para and symp ganglia
Parasympathetic and sympathetic inhibition – very broad effects
*Tremors, confusion, seizures, mania, depression
*Improve absorption from GI tract (oral – 12 hours), adjunct therapy for hypertension and peripheral vascular disease
Trimethaphan
*Cholinergic antagonist – nicotinic selective – sulfonium- nondepolarizing competitive antagonists
*Inhibit neurotransmission by N1 receptors in both para and symp ganglia
Parasympathetic and sympathetic inhibition – very broad effects
*Excessive hypotension and possible brain anoxia
*IV infusion use (lasts minutes), adjunct therapy for hypertension and peripheral vascular disease, short-acting IV to minimize blood loss in surgery
Succinylcholine
*Cholinergic antagonist – depolarizing, noncompetitive receptor agonist for ACh action
*Systemic activity is very short-lived (rapid hydrolysis by plasma ChE)
Parasympathetic inhibition
*Don’t use with CHF, burns, trauma, or neuromuscular disease patients
*Muscle relaxation for surgery, tracheal intubation, control of ventilation, convulsions
Curare
- Cholinergic antagonist – non-depolarizing – long acting, benzylisoquinoline
- Compete with ACh for binding to N2 receptor sites - motor weakness – total flaccid paralysis
- Check respirations and ventilation, bronchial airway obstruction
- Muscle relaxation for surgery, tracheal intubation, control of ventilation, convulsions
Atracurium
- Cholinergic antagonist – non-depolarizing
- Compete with ACh for binding to N2 receptor sites - motor weakness – total flaccid paralysis
- Check respirations and ventilation, bronchial airway obstruction
- Muscle relaxation for surgery, tracheal intubation, control of ventilation, convulsions
Cisatracurium
- Cholinergic antagonist – non-depolarizing – intermediate length, benzylisoquinoline
- Compete with ACh for binding to N2 receptor sites - motor weakness – total flaccid paralysis
- Check respirations and ventilation, bronchial airway obstruction
- Muscle relaxation for surgery, tracheal intubation, control of ventilation, convulsions
Mivacurium
- Cholinergic antagonist – non-depolarizing – short acting, benzylisoquinoline
- Compete with ACh for binding to N2 receptor sites - motor weakness – total flaccid paralysis
- Check respirations and ventilation, bronchial airway obstruction
- Muscle relaxation for surgery, tracheal intubation, control of ventilation, convulsions
Pancuronium
- Cholinergic antagonist – non-depolarizing – long acting, ammonio steroid
- Compete with ACh for binding to N2 receptor sites - motor weakness – total flaccid paralysis
- Check respirations and ventilation, bronchial airway obstruction
- Muscle relaxation for surgery, tracheal intubation, control of ventilation, convulsions
Vecuronium
- Cholinergic antagonist – non-depolarizing – intermediate length, ammonio steroid
- Compete with ACh for binding to N2 receptor sites - motor weakness – total flaccid paralysis
- Check respirations and ventilation, bronchial airway obstruction
- Muscle relaxation for surgery, tracheal intubation, control of ventilation, convulsions
