Autonomics Flashcards
- Atropine is used to counteract:
a) High sympathetic activity
b) Excessively high parasympathetic activity
c) Muscle contractions
d) Neurotransmitter depletion
b) Excessively high parasympathetic activity
Rationale: Atropine is administered when parasympathetic activity is excessively high, such as in severe bradycardia, by blocking muscarinic receptors.
- Nicotinic receptors are primarily located in:
a) The heart
b) Smooth muscles
c) Autonomic ganglia of the ANS and NMJ
d) The liver
c) Autonomic ganglia of the ANS and NMJ
Rationale: Nicotinic receptors are located in the autonomic ganglia of the ANS, neuromuscular junctions (NMJ), and adrenal medulla.
- The action of muscarinic receptors in the heart is primarily:
a) Excitatory
b) Inhibitory
c) Neutral
d) Variable
b) Inhibitory
Rationale: In the heart, muscarinic receptors have an inhibitory effect, but they are excitatory in smooth muscle and glands.
- Ganglionic blockers such as hexamethonium act by blocking:
a) Muscarinic receptors
b) Nicotinic receptors
c) Beta receptors
d) Alpha receptors
b) Nicotinic receptors
Rationale: Ganglionic blockers like hexamethonium block nicotinic receptors, particularly at autonomic ganglia.
- Atropine’s mechanism of action involves:
a) Exciting muscarinic receptors
b) Blocking muscarinic receptors
c) Increasing neurotransmitter release
d) Blocking nicotinic receptors
b) Blocking muscarinic receptors
Rationale: Atropine acts by blocking muscarinic receptors, thus reducing parasympathetic activity.
- In smooth muscles and glands, muscarinic receptors cause:
a) Inhibition
b) Excitation
c) No change in activity
d) Stabilization
b) Excitation
Rationale: Muscarinic receptors are inhibitory in the heart but excitatory in smooth muscles and glands.
- The effect of activating nicotinic receptors at the NMJ is:
a) Relaxation
b) Excitation
c) Inhibition
d) Stabilization
b) Excitation
Rationale: Nicotinic receptors at the NMJ and in autonomic ganglia primarily cause excitation.
- Atropine is contraindicated in patients with:
a) Low heart rate
b) High heart rate
c) Closed-angle glaucoma
d) Open-angle glaucoma
c) Closed-angle glaucoma
Rationale: Atropine is contraindicated in closed-angle glaucoma due to the risk of increasing intraocular pressure.
- In the SA node, muscarinic receptors’ action leads to:
a) Opening of sodium channels
b) Inhibition of adenylate cyclase and opening of potassium channels
c) Activation of calcium channels
d) Excitation of the heart muscle
b) Inhibition of adenylate cyclase and opening of potassium channels
Rationale: Muscarinic receptors in the SA node inhibit adenylate cyclase, leading to the opening of potassium channels.
- The role of acetylcholine in the cholinergic system is to:
a) Inhibit muscle contraction
b) Act as a neurotransmitter
c) Block receptor activity
d) Decrease heart rate
b) Act as a neurotransmitter
Rationale: Acetylcholine is the primary neurotransmitter in the cholinergic system, playing a crucial role in various physiological functions.
- Hexamethonium’s primary action in the cholinergic system is to:
a) Increase acetylcholine release
b) Block nicotinic receptors at autonomic ganglia
c) Stimulate muscarinic receptors
d) Increase heart rate
b) Block nicotinic receptors at autonomic ganglia
Rationale: Hexamethonium acts as a ganglionic blocker by blocking nicotinic receptors at autonomic ganglia.
- In the treatment of bradycardia, atropine is effective because it:
a) Decreases heart rate further
b) Increases heart rate
c) Has no effect on heart rate
d) Stabilizes heart rate
b) Increases heart rate
Rationale: Atropine is used in severe bradycardia to increase heart rate by reducing parasympathetic activity.
- Muscarinic receptors in smooth muscles and glands are activated to cause:
a) Decreased intracellular calcium
b) Increased intracellular IP3 and calcium
c) Stabilization of membrane potential
d) Decrease in glandular secretions
b) Increased intracellular IP3 and calcium
Rationale: Activation of muscarinic receptors in smooth muscles and glands leads to increased IP3 and intracellular calcium levels.
- The primary effect of nicotinic receptors activation at the adrenal medulla is:
a) Decreased adrenaline release
b) Increased adrenaline release
c) No effect on adrenaline release
d) Stabilization of adrenaline levels
b) Increased adrenaline release
Rationale: Activation of nicotinic receptors at the adrenal medulla typically leads to increased adrenaline release.
- Atropine’s ability to increase sympathetic features is due to its action of:
a) Stimulating muscarinic receptors
b) Blocking muscarinic receptors
c) Activating nicotinic receptors
d) Inhibiting acetylcholine synthesis
b) Blocking muscarinic receptors
Rationale: Atropine increases sympathetic features by blocking muscarinic receptors, reducing parasympathetic activity.
- The use of hexamethonium in the cholinergic system primarily results in:
a) Decreased sympathetic activity
b) Increased parasympathetic activity
c) Reduced neurotransmitter release
d) Enhanced neurotransmitter release
c) Reduced neurotransmitter release
Rationale: Hexamethonium reduces neurotransmitter release by blocking nicotinic receptors at autonomic ganglia.
- In glaucoma treatment, the role of cholinergic drugs like Pilocarpine is to:
a) Decrease intraocular pressure
b) Increase intraocular pressure
c) Dilate the pupil
d) Improve vision clarity
a) Decrease intraocular pressure
Rationale: Cholinergic drugs like Pilocarpine decrease intraocular pressure by enhancing the drainage of aqueous humor.
- Atropine’s use in severe bradycardia works by:
a) Decreasing cardiac output
b) Increasing cardiac output
c) Stabilizing heart rate
d) Decreasing heart rate
b) Increasing cardiac output
Rationale: Atropine is used in severe bradycardia to increase heart rate and cardiac output by reducing parasympathetic activity.
- The action of muscarinic receptors in the heart primarily results in:
a) Increased heart rate
b) Decreased heart rate
c) No change in heart rate
d) Irregular heart rhythm
b) Decreased heart rate
Rationale: Muscarinic receptors in the heart primarily have an inhibitory effect, leading to a decreased heart rate.
- The therapeutic action of acetylcholine in the cholinergic system includes:
a) Contracting smooth muscles
b) Relaxing smooth muscles
c) Blocking neurotransmitter release
d) Increasing blood pressure
a) Contracting smooth muscles
Rationale: Acetylcholine in the cholinergic system plays a role in contracting smooth muscles, among other functions.
- What is the primary neurotransmitter of the parasympathetic nervous system?
a) Dopamine
b) Serotonin
c) Acetylcholine
d) Norepinephrine
c) Acetylcholine
Rationale: Acetylcholine is the primary neurotransmitter of the parasympathetic nervous system, responsible for stimulating parasympathetic activities.
- Which type of drug would likely decrease heart rate?
a) Cholinergic Agonist
b) Cholinergic Antagonist
c) Adrenergic Agonist
d) Adrenergic Antagonist
a) Cholinergic Agonist
Rationale: Cholinergic agonists stimulate parasympathetic activity, leading to effects like decreased heart rate.
- Which drug category is known to dilate pupils?
a) Cholinergic Agonist
b) Cholinergic Antagonist
c) Adrenergic Agonist
d) Adrenergic Antagonist
c) Adrenergic Agonist
- Which medication type is used to manage asthma by expanding airways?
a) Cholinergic Agonist
b) Cholinergic Antagonist
c) Adrenergic Agonist
d) Adrenergic Antagonist
c) Adrenergic Agonist
Rationale: Adrenergic agonists increase sympathetic responses, such as expanded airways, useful in asthma management.
- What effect would an adrenergic antagonist have on blood pressure?
a) Increase
b) Decrease
c) No change
d) Variable
b) Decrease
Rationale: Adrenergic antagonists inhibit sympathetic activity, leading to effects like decreased blood pressure.
- Which type of drug would likely increase glandular secretions?
a) Cholinergic Agonist
b) Cholinergic Antagonist
c) Adrenergic Agonist
d) Adrenergic Antagonist
a) Cholinergic Agonist
Rationale: Cholinergic agonists stimulate parasympathetic activities, leading to increased glandular secretions.
- What is the primary action of adrenergic antagonists?
a) Stimulate sympathetic activity
b) Inhibit parasympathetic activity
c) Inhibit sympathetic activity
d) Stimulate parasympathetic activity
c) Inhibit sympathetic activity
Rationale: Adrenergic antagonists block the action of norepinephrine and adrenaline, reducing sympathetic activity.
- A drug that mimics the action of norepinephrine would be categorized as:
a) Cholinergic Agonist
b) Cholinergic Antagonist
c) Adrenergic Agonist
d) Adrenergic Antagonist
c) Adrenergic Agonist
Rationale: Adrenergic agonists enhance or mimic the effects of norepinephrine and adrenaline.
- Which medication class is primarily used in heart conditions to boost sympathetic activity?
a) Cholinergic Agonist
b) Cholinergic Antagonist
c) Adrenergic Agonist
d) Adrenergic Antagonist
c) Adrenergic Agonist
Rationale: Adrenergic agonists are often used in heart conditions to enhance sympathetic responses.
- What is the effect of cholinergic antagonists on digestion?
a) Increase
b) Decrease
c) No change
d) Variable
b) Decrease
Rationale: Cholinergic antagonists induce sympathetic-like effects, including decreased digestive activity.
- Which drugs mimic the effects of adrenaline?
a) Cholinergic Agonist
b) Cholinergic Antagonist
c) Adrenergic Agonist
d) Adrenergic Antagonist
c) Adrenergic Agonist
Rationale: Adrenergic agonists stimulate or enhance the effects of adrenaline.
- What is the primary effect of a cholinergic antagonist on the heart rate?
a) Increase
b) Decrease
c) No change
d) Variable
a) Increase
Rationale: By blocking the action of acetylcholine, cholinergic antagonists induce an increase in heart rate.
- What is the primary action of cholinergic agonists?
a) Inhibit the parasympathetic nervous system
b) Stimulate the sympathetic nervous system
c) Mimic the actions of acetylcholine
d) Block acetylcholine receptors
c) Mimic the actions of acetylcholine
Rationale: Cholinergic agonists stimulate the parasympathetic nervous system by mimicking the actions of acetylcholine.
- Which class of cholinergic agonists directly binds to acetylcholine receptors?
a) Indirect Acting Cholinergic Agonists
b) Direct Acting Cholinergic Agonists
c) Organophosphates
d) Myasthenia Gravis Treatments
b) Direct Acting Cholinergic Agonists
Rationale: Direct acting cholinergic agonists bind directly to and activate acetylcholine receptors.
- Pilocarpine, used to treat glaucoma, belongs to which category of cholinergic agonists?
a) Direct Acting
b) Indirect Acting
c) Organophosphates
d) Myasthenia Gravis Treatments
a) Direct Acting
Rationale: Pilocarpine is a direct-acting cholinergic agonist, used for glaucoma treatment.
- Which is an example of an indirect acting cholinergic agonist used in myasthenia gravis?
a) Acetylcholine
b) Carbachol
c) Neostigmine
d) Nicotine
c) Neostigmine
- Organophosphates, a category of cholinergic agonists, are primarily used as:
a) Cardiac medications
b) Pesticides
c) Antidepressants
d) Antihistamines
b) Pesticides
Rationale: Organophosphates, which are a type of indirect acting cholinergic agonist, are typically used as pesticides.
- What is the mechanism of action of indirect acting cholinergic agonists?
a) Binding to acetylcholine receptors
b) Inhibiting the breakdown of acetylcholine
c) Blocking sympathetic neurotransmitters
d) Enhancing the release of acetylcholine
b) Inhibiting the breakdown of acetylcholine
Rationale: Indirect acting cholinergic agonists increase acetylcholine levels by inhibiting its breakdown.
- Which of the following is a direct acting cholinergic agonist?
a) Isoflurophate
b) Bethanechol
c) Edrophonium
d) Parathion
b) Bethanechol
Rationale: Bethanechol is a direct acting cholinergic agonist.
- Neostigmine is used in the treatment of:
a) Hypertension
b) Myasthenia Gravis
c) Glaucoma
d) Depression
b) Myasthenia Gravis
Rationale: Neostigmine is an indirect acting cholinergic agonist used primarily in the management of myasthenia gravis.
- Drugs with names ending in “-chol” are generally:
a) Indirect Acting Cholinergic Agonists
b) Direct Acting Cholinergic Agonists
c) Organophosphates
d) Sympathetic Agonists
b) Direct Acting Cholinergic Agonists
Rationale: Drugs ending in “-chol” are typically direct acting cholinergic agonists, reflecting their relation to acetylcholine.
- Which drug is an organophosphate and an indirect acting cholinergic agonist?
a) Carbachol
b) Methacholine
c) Ecothiophate
d) Pilocarpine
c) Ecothiophate
Rationale: Ecothiophate/ Isoflurophate is an organophosphate and an indirect acting cholinergic agonist.
- Methacholine, a cholinergic agonist, is classified as:
a) Direct Acting
b) Indirect Acting
c) Organophosphate
d) Myasthenia Gravis Treatment
a) Direct Acting
- What is the primary reason pure acetylcholine is not used as a drug?
a) It has a short half-life
b) It is too expensive to synthesize
c) It causes severe side effects
d) It is ineffective in the human body
a) It has a short half-life
Rationale: Acetylcholine has a very short half-life, making it impractical to use in drug form. Analogues and derivatives are used instead.
- Which direct acting cholinergic agonist is the drug of choice for treating glaucoma?
a) Bethanechol
b) Pilocarpine
c) Carbachol
d) Methacholine
b) Pilocarpine
Rationale: Pilocarpine is primarily used for treating glaucoma due to its ability to stimulate miosis and facilitate the opening of the trabecular meshwork.
- What is the effect of acetylcholine on the cardiovascular system (CVS)?
a) Increases heart rate and contractility
b) Decreases heart rate and contractility
c) Has no effect on heart rate
d) Increases blood pressure
b) Decreases heart rate and contractility
Rationale: Acetylcholine affects the CVS by decreasing heart rate and contractility, and lowering blood pressure.
- Bethanechol is used to treat:
a) Asthma
b) Urinary retention
c) Glaucoma
d) High blood pressure
b) Urinary retention
Rationale: Bethanechol is used to treat urinary retention by activating smooth muscle in the bladder and bowel, facilitating voiding and bowel movements.
- What action does carbachol have on the eye?
a) Decreases intraocular pressure
b) Causes pupil dilation
c) Reduces tear production
d) Improves vision clarity
a) Decreases intraocular pressure
Rationale: Carbachol activates the ciliary muscle of the eye, which helps in the management of open-angle glaucoma, and the pupillary sphincter, used for narrow-angle glaucoma.
- What is a potential CNS effect of pilocarpine?
a) Sedation
b) Hallucinations and convulsions
c) Memory enhancement
d) Mood elevation
b) Hallucinations and convulsions
Rationale: Pilocarpine can penetrate the CNS and may cause hallucinations and convulsions; overdose can lead to severe hallucinations.
- The methacholine challenge test is used to diagnose:
a) Urinary incontinence
b) Asthma and bronchial hyperactivity
c) Glaucoma
d) Cardiac arrhythmias
b) Asthma and bronchial hyperactivity
Rationale: The methacholine challenge test, which provokes bronchoconstriction, is used to diagnose asthma and bronchial hyperactivity.
- Acetylcholine’s effect on the gastrointestinal (GI) system is to:
a) Decrease motility
b) Increase motility
c) Cause constipation
d) Reduce acid secretion
b) Increase motility
Rationale: Acetylcholine increases motility in the GI system.
- Which drug causes miosis (pupil constriction)?
a) Bethanechol
b) Pilocarpine
c) Carbachol
d) Methacholine
b) Pilocarpine
Rationale: Pilocarpine stimulates miosis, which is utilized in the treatment of glaucoma.
- The mnemonic “BBB” for Bethanechol stands for:
a) Brain, Blood, Breath
b) Bethanechol, Bladder, Bowel
c) Bethanechol, Blood pressure, Bronchoconstriction
d) Brain, Bladder, Bronchi
b) Bethanechol, Bladder, Bowel
Rationale: The mnemonic “BBB” for Bethanechol helps remember its use in treating conditions related to the bladder and bowel.
- Acetylcholine’s effect on the endocrine system is:
a) Inhibiting insulin release
b) Stimulating the release of epinephrine leading to sweating
c) Decreasing cortisol levels
d) Enhancing thyroid hormone secretion
b) Stimulating the release of epinephrine leading to sweating
Rationale: Acetylcholine stimulates the release of epinephrine, leading to sweating. This response is not purely sympathetic.
- The primary action of carbachol in the treatment of glaucoma is:
a) Reducing redness and irritation
b) Improving vision clarity
c) Decreasing intraocular pressure
d) Increasing tear production
c) Decreasing intraocular pressure
Rationale: Carbachol is used in glaucoma treatment primarily for its action in decreasing intraocular pressure.
- Acetylcholine’s effect on the pulmonary system is to:
a) Decrease secretion in the bronchioles
b) Increase secretion in the bronchioles
c) Cause bronchodilation
d) Reduce airway inflammation
b) Increase secretion in the bronchioles
Rationale: Acetylcholine increases secretion in the bronchioles as part of its effect on the pulmonary system.
- The effect of acetylcholine on the peripheral nervous system (PNS) is to:
a) Induce muscle relaxation
b) Induce muscle contraction
c) Decrease nerve signal transmission
d) Increase pain sensation
b) Induce muscle contraction
Rationale: In the PNS, acetylcholine induces muscle contraction.
- Carbachol’s use in eye surgery is due to its ability to:
a) Improve vision clarity
b) Induce miosis
c) Prevent infection
d) Reduce inflammation
b) Induce miosis
Rationale: Carbachol is used in eye surgery for its ability to induce miosis.
- Which of the following is a role of acetylcholine in the central nervous system (CNS)?
a) Neurotransmission
b) Blood-brain barrier protection
c) Cognitive impairment
d) Sleep induction
a) Neurotransmission
Rationale: Acetylcholine is involved in neurotransmission within the CNS.
- The usage of methacholine as a diagnostic tool is based on its ability to:
a) Induce bronchodilation
b) Provoke bronchoconstriction
c) Stimulate the heart
d) Relax smooth muscles
b) Provoke bronchoconstriction
Rationale: Methacholine is used to diagnose asthma and bronchial hyperactivity due to its ability to provoke bronchoconstriction.
- Pilocarpine’s mode of action in treating glaucoma involves:
a) Reducing inflammation in the eye
b) Stimulating miosis and facilitating the opening of the trabecular meshwork
c) Lowering blood glucose levels
d) Enhancing tear production
b) Stimulating miosis and facilitating the opening of the trabecular meshwork
Rationale: Pilocarpine treats glaucoma by stimulating miosis and facilitating the opening of the trabecular meshwork at the Canal of Schlemm.
- Bethanechol’s action on the bladder and bowel is to:
a) Activate smooth muscle
b) Inhibit smooth muscle
c) Decrease secretions
d) Increase pain sensation
a) Activate smooth muscle
Rationale: Bethanechol activates smooth muscle in the bladder and bowel, aiding in voiding and bowel movements.
- The primary reason for the limited use of carbachol is due to its:
a) High cost
b) Specific actions and side effects
c) Lack of efficacy
d) Drug interactions
b) Specific actions and side effects
Rationale: Carbachol’s limited use is attributed to its specific actions and side effects, making it less suitable for general use compared to other medications.
- What is the mechanism of action of organophosphates?
a) They stimulate acetylcholine receptors directly.
b) They reversibly inhibit acetylcholinesterase.
c) They irreversibly inhibit acetylcholinesterase.
d) They increase the breakdown of acetylcholine.
c) They irreversibly inhibit acetylcholinesterase.
Rationale: Organophosphates bind covalently to acetylcholinesterase, irreversibly inhibiting it and thus increasing acetylcholine levels.
- Which antidote is used to counteract organophosphate poisoning?
a) Atropine
b) Pralidoxime
c) Epinephrine
d) Naloxone
b) Pralidoxime
Rationale: Pralidoxime is used as an antidote to organophosphate poisoning.
- What is the duration of acetylcholinesterase inhibition by organophosphates?
a) 24 hours
b) About a week
c) A month
d) Indefinitely
b) About a week
Rationale: The inhibition of acetylcholinesterase by organophosphates typically lasts for about a week.
- Initial treatment steps for organophosphate poisoning include:
a) Immediate administration of pralidoxime
b) Washing the patient to remove any organophosphate from the skin
c) Performing gastric lavage
d) Administering activated charcoal
b) Washing the patient to remove any organophosphate from the skin
Rationale: The initial steps in real-world treatment of organophosphate poisoning include washing the patient to remove the chemical from the skin.
- Which of the following is an example of an organophosphate used in the treatment of glaucoma?
a) Isoflurophate
b) Neostigmine
c) Bethanechol
d) Pilocarpine
a) Isofluorophate
Rationale: Isofluorophate is an example of an organophosphate used occasionally in the treatment of glaucoma.
- The DUMBELS symptomatology in organophosphate poisoning includes:
a) Dizziness, Urticaria, Muscle cramps
b) Diarrhea, Urination, Miosis
c) Drowsiness, Urinary retention, Mydriasis
d) Dermatitis, Ulcers, Muscle weakness
b) Diarrhea, Urination, Miosis
Rationale: DUMBELS in organophosphate poisoning stands for Diarrhea, Urination, Miosis, Bronchoconstriction, Excitation of skeletal muscles, Lacrimation, Salivation and sweating.
- What is the effect of organophosphates on blood pressure?
a) Increase
b) Decrease
c) No change
d) Variable effects
b) Decrease
Rationale: Organophosphate poisoning can lead to decreased blood pressure as part of the DUMBELS symptomatology.
- What role does atropine play in the treatment of organophosphate poisoning?
a) It serves as the primary antidote.
b) It is used to counteract falling blood pressure and heart rate.
c) It reverses the inhibition of acetylcholinesterase.
d) It removes organophosphates from the body.
b) It is used to counteract falling blood pressure and heart rate.
Rationale: Atropine may be administered in organophosphate poisoning based on symptoms such as falling blood pressure and heart rate.
- Which organophosphate effect is considered a sympathetic response?
a) Diarrhea
b) Urination
c) Sweating
d) Miosis
c) Sweating (Not Purely SNS)
Rationale: While most effects of organophosphate poisoning are parasympathetic, sweating is a sympathetic response.
- In the context of examinations, what is important to remember about organophosphate poisoning?
a) The immediate administration of atropine
b) The use of pralidoxime as an antidote
c) The necessity of immediate gastric lavage
d) The application of activated charcoal
b) The use of pralidoxime as an antidote
Rationale: For exam purposes, it is important to remember that pralidoxime is the antidote for organophosphate poisoning.
- What is a symptom of organophosphate poisoning related to the pulmonary system?
a) Increased lung capacity
b) Bronchoconstriction
c) Decreased mucus production
d) Bronchodilation
b) Bronchoconstriction
Rationale: Bronchoconstriction is a symptom of organophosphate poisoning affecting the pulmonary system.
- Echothiophate, an organophosphate, is used in the treatment of:
a) Myasthenia Gravis
b) Glaucoma
c) Urinary retention
d) Asthma
b) Glaucoma
Rationale: Echothiophate is an organophosphate occasionally used in the treatment of glaucoma.
- What is the effect of organophosphates on salivation?
a) Decrease
b) Increase
c) No change
d) Variable
b) Increase
Rationale: Organophosphate poisoning leads to increased salivation as part of the DUMBELS symptomatology.
- Further management steps for organophosphate poisoning include:
a) Administration of insulin
b) Gastric lavage and activated charcoal
c) Immediate surgery
d) High doses of vitamin supplements
b) Gastric lavage and activated charcoal
Rationale: Gastric lavage and administration of activated charcoal are further steps in the treatment of organophosphate poisoning.
- What is the effect of organophosphates on the eyes?
a) Causes mydriasis (pupil dilation)
b) No effect
c) Causes miosis (pupil constriction)
d) Improves vision clarity
c) Causes miosis (pupil constriction)
Rationale: Organophosphates cause miosis, or pupil constriction, as part of their effect on the body.
- The main reason for performing gastric lavage in organophosphate poisoning is to:
a) Relieve abdominal pain
b) Remove the toxin from the stomach
c) Alleviate nausea
d) Counteract acidosis
b) Remove the toxin from the stomach
Rationale: Gastric lavage is performed to remove the organophosphate toxin from the stomach.
- The use of activated charcoal in organophosphate poisoning is primarily to:
a) Neutralize the toxin
b) Absorb the toxin from the gastrointestinal tract
c) Induce vomiting
d) Provide nutritional support
b) Absorb the toxin from the gastrointestinal tract
Rationale: Activated charcoal is used in organophosphate poisoning to absorb the toxin from the gastrointestinal tract.
- The excitation of skeletal muscles in organophosphate poisoning leads to:
a) Increased strength and endurance
b) Muscle spasms and twitching
c) Muscle relaxation
d) Decreased muscle tone
b) Muscle spasms and twitching
Rationale: Excitation of skeletal muscles in organophosphate poisoning can lead to muscle spasms and twitching.
- In organophosphate poisoning, the role of washing the patient (ligo) is to:
a) Cool down the body temperature
b) Remove any organophosphate from the skin
c) Relieve itching and discomfort
d) Stimulate blood circulation
b) Remove any organophosphate from the skin
Rationale: Washing the patient in organophosphate poisoning is crucial to remove the chemical from the skin and prevent its transfer to healthcare providers.
- Lacrimation (tearing) in organophosphate poisoning is due to:
a) Irritation of the eye
b) Increased parasympathetic activity
c) An allergic reaction
d) Dehydration
b) Increased parasympathetic activity
Rationale: Lacrimation or increased tearing in organophosphate poisoning is a result of increased parasympathetic activity.
- What is the primary mechanism of action of reversible indirect agonists?
a) Decreasing acetylcholine synthesis
b) Reversibly inhibiting acetylcholinesterase
c) Blocking acetylcholine receptors
d) Increasing the breakdown of acetylcholine
b) Reversibly inhibiting acetylcholinesterase
Rationale: These drugs increase acetylcholine levels by reversibly inhibiting acetylcholinesterase, leading to an accumulation of acetylcholine.
- Neostigmine is used primarily for the treatment of:
a) Hypertension
b) Myasthenia Gravis
c) Glaucoma
d) Depression
b) Myasthenia Gravis
Rationale: Neostigmine is the drug of choice for the treatment of myasthenia gravis.
- What is the duration of effect of Pyridostigmine?
a) 30 minutes to 1 hour
b) 1-2 hours
c) 3-6 hours
d) Over 6 hours
c) 3-6 hours
Rationale: Pyridostigmine has a long-lasting effect, typically 3-6 hours, and is used for long-term maintenance treatment of myasthenia gravis.
- Edrophonium is used diagnostically to:
a) Confirm a diagnosis of hypertension
b) Diagnose myasthenia gravis
c) Diagnose glaucoma
d) Evaluate liver function
b) Diagnose myasthenia gravis
Rationale: Edrophonium is administered to diagnose myasthenia gravis due to its brief increase in endogenous acetylcholine.
- Physostigmine is an effective antidote for overdoses of:
a) Benzodiazepines
b) Opioids
c) Atropine, phenothiazines, and TCAs
d) Beta-blockers
c) Atropine, phenothiazines, and TCAs
Rationale: Physostigmine can cross the blood-brain barrier and is effective for overdoses of atropine, phenothiazines, and tricyclic antidepressants (TCAs).
- A secondary use of Physostigmine is:
a) Treating hypertension
b) As a second-choice drug for glaucoma
c) Managing diabetes
d) Treating asthma
b) As a second-choice drug for glaucoma
Rationale: Physostigmine is used as a second-choice drug for glaucoma due to its ability to increase acetylcholine levels.
- Which drug is known for its brief increase in endogenous acetylcholine?
a) Neostigmine
b) Pyridostigmine
c) Edrophonium
d) Physostigmine
c) Edrophonium
Shortest T1/2 (Duration of action)
Rationale: Edrophonium causes a brief increase in endogenous acetylcholine and is used diagnostically for myasthenia gravis.
- The mnemonic “Neo the Cure” refers to:
a) Neostigmine used for hypertension
b) Neostigmine used for myasthenia gravis
c) Neostigmine used for glaucoma
d) Neostigmine used for diabetes
b) Neostigmine used for myasthenia gravis
Rationale: “Neo the Cure” is a mnemonic indicating that Neostigmine is the drug of choice for myasthenia gravis treatment.
- Pyridostigmine’s primary application is:
a) Short-term relief of hypertension
b) Long-term maintenance treatment of myasthenia gravis
c) Emergency treatment of glaucoma
d) Management of depression
b) Long-term maintenance treatment of myasthenia gravis
Rationale: Pyridostigmine is primarily used for the long-term maintenance treatment of myasthenia gravis.
- Which reversible indirect agonist is not recommended for myasthenia gravis?
a) Neostigmine
b) Pyridostigmine
c) Edrophonium
d) Physostigmine
d) Physostigmine
Rationale: Physostigmine is not recommended for myasthenia gravis treatment.
- One of the cautionary notes for Edrophonium is that it can:
a) Cause hypertension
b) Worsen a cholinergic crisis
c) Lead to severe depression
d) Increase blood sugar levels
b) Worsen a cholinergic crisis
Rationale: Edrophonium can worsen a cholinergic crisis if misused, particularly in the context of myasthenia gravis.
- What is a potential side effect of Physostigmine?
a) Causing cataracts and muscle paralysis
b) Inducing sleep
c) Reducing heart rate
d) Causing weight gain
a) Causing cataracts and muscle paralysis
Rationale: Physostigmine can cause side effects such as cataracts and muscle paralysis.
- Neostigmine is also used as an antidote for:
a) Opioid overdose
b) Benzodiazepine overdose
c) Neuromuscular junction (NMJ) blockade post-operation
d) Atropine overdose
c) Neuromuscular junction (NMJ) blockade post-operation
Rationale: Neostigmine is used for the reversal of neuromuscular junction blockade post-operation.
- The action of Pyridostigmine is to:
a) Decrease muscle strength
b) Increase endogenous acetylcholine, enhancing muscle strength
c) Block acetylcholine receptors in the muscles
d) Reduce blood pressure
b) Increase endogenous acetylcholine, enhancing muscle strength
Rationale: Pyridostigmine increases endogenous acetylcholine, which enhances muscle strength, particularly in the treatment of myasthenia gravis.
- Physostigmine’s ability to cross the Blood-Brain Barrier (BBB) can lead to:
a) Improved cognitive function
b) Reduced anxiety
c) Seizures
d) Enhanced mood
c) Seizures
Rationale: Due to its ability to cross the BBB, Physostigmine can lead to seizures as a side effect.
- “Dodong the Long Name” mnemonic is associated with:
a) Neostigmine
b) Pyridostigmine
c) Edrophonium
d) Physostigmine
b) Pyridostigmine
Rationale: The mnemonic “Dodong the Long Name” refers to Pyridostigmine, which is used for long-term maintenance therapy in myasthenia gravis.
- The primary role of Edrophonium in myasthenia gravis is:
a) Long-term maintenance therapy
b) Short-term symptomatic relief
c) Diagnostic use
d) As an antidote for NMJ blockade
c) Diagnostic use
Rationale: Edrophonium is used primarily for the diagnostic evaluation of myasthenia gravis.
- Neostigmine’s use in postoperative care is primarily for:
a) Pain relief
b) Treating hypertension
c) Treating neurogenic ileus and urinary retention
d) Accelerating wound healing
c) Treating neurogenic ileus and urinary retention
Rationale: Neostigmine is used in postoperative care for the treatment of neurogenic ileus and urinary retention.
- A caution with the use of Physostigmine is that it:
a) Can lead to severe dehydration
b) May cause irreversible muscle damage
c) Can lead to seizures due to CNS penetration
d) Causes chronic insomnia
c) Can lead to seizures due to CNS penetration
Rationale: Due to its ability to cross the blood-brain barrier, Physostigmine can lead to seizures.
- What is a common use of atropine in emergency medicine?
a) To reduce high blood pressure
b) To increase heart rate in bradycardia
c) To manage hypertension
d) As a pain reliever
b) To increase heart rate in bradycardia
Rationale: Atropine is administered in cases of bradycardia to increase heart rate.
- In ophthalmology, atropine is used for:
a) Improving vision
b) Reducing intraocular pressure
c) Dilating pupils for eye examinations
d) Treating infections
c) Dilating pupils for eye examinations
Rationale: Atropine is used in ophthalmology, particularly in fundoscopy, to dilate pupils.
- Atropine is an antidote for which type of poisoning?
a) Benzodiazepine
b) Opioid
c) Organophosphate
d) Alcohol
c) Organophosphate
Rationale: Atropine is used as an antidote for organophosphate poisoning.
- The plant from which atropine is derived is:
a) Cannabis sativa
b) Papaver somniferum
c) Atropa belladonna
d) Eucalyptus globulus
c) Atropa belladonna
Rationale: Atropine is derived from the plant Atropa belladonna.
- Atropine’s mechanism of action involves:
a) Stimulating muscarinic receptors
b) Blocking muscarinic receptors
c) Inhibiting acetylcholinesterase
d) Activating nicotinic receptors
b) Blocking muscarinic receptors
Rationale: Atropine works by blocking the effects of acetylcholine on muscarinic receptors.
- What is the duration of atropine’s effect in the body?
a) 1 hour
b) 2-3 hours
c) About 4 hours
d) Over 6 hours
c) About 4 hours
Rationale: Atropine lasts about 4 hours in the body, but its effect can persist for up to 72 hours in the eyes.
- Atropine is contraindicated in individuals with:
a) Hypertension
b) Diabetes
c) Narrow-angle glaucoma
d) Asthma
c) Narrow-angle glaucoma
Rationale: Atropine is not recommended for individuals with narrow-angle glaucoma due to the risk of acute crisis.
- One of the toxicity symptoms of atropine is:
a) Excessive salivation
b) Dry mouth
c) Increased urination
d) Excessive sweating
b) Dry mouth
Rationale: “Dry as a Bone” refers to the symptom of dry mouth in atropine toxicity.
- Atropine can cause which central nervous system effect in overdose?
a) Sedation
b) Tachycardia
c) Paralysis
d) Reduced reflexes
b) Tachycardia
Rationale: In overdose, atropine CANNOT cross the blood-brain barrier BUT can cause tachycardia.
- What is the effect of atropine on gastrointestinal procedures?
a) Increases secretions
b) Reduces secretions
c) Stimulates digestion
d) Causes constipation
b) Reduces secretions
Rationale: Atropine is used in gastrointestinal procedures to reduce secretions.
- “Mad as a Hatter” refers to which side effect of atropine?
a) Hypertension
b) Hallucinations or delirium
c) Insomnia
d) Anxiety
b) Hallucinations or delirium
Rationale: “Mad as a Hatter” describes the potential for hallucinations or delirium in atropine toxicity.
- The symptomatic effect of atropine on the bladder is:
a) Increased urination
b) Urinary retention
c) Reducing urinary urgency
d) Causing incontinence
c) Reducing urinary urgency
Rationale: Atropine reduces urinary urgency by alleviating bladder spasms.
- Which of the following is another muscarinic antagonist used in the treatment of Parkinson’s disease?
a) Benztropine
b) Thorazine (Chlorpromazine)
c) Diphenhydramine
d) Ipratropium
a) Benztropine
Rationale: Benztropine is a muscarinic antagonist used in the treatment of Parkinson’s disease.
- Which medication is a muscarinic antagonist used as an antipsychotic?
a) Benztropine
b) Thorazine (Chlorpromazine)
c) Diphenhydramine
d) Ipratropium
b) Thorazine (Chlorpromazine)
Rationale: Thorazine (Chlorpromazine) is an antipsychotic medication that also acts as a muscarinic antagonist.
- Diphenhydramine, a muscarinic antagonist, is commonly used for:
a) Asthma
b) Allergies
c) Parkinson’s disease
d) Glaucoma
b) Allergies
Rationale: Diphenhydramine is an antihistamine commonly used for allergies.
- Ipratropium, as a muscarinic antagonist, is used primarily for:
a) Treating hypertension
b) Managing diabetes
c) As a bronchodilator in asthma
d) Treating narcolepsy
c) As a bronchodilator in asthma
Rationale: Ipratropium is used as a bronchodilator in the treatment of asthma.
- The term “Red as a Beet” in atropine toxicity refers to:
a) Skin irritation
b) Tachycardia and cutaneous vasodilation
c) Allergic reactions
d) Elevated body temperature
b) Tachycardia and cutaneous vasodilation
Rationale: “Red as a Beet” describes tachycardia and cutaneous vasodilation seen in atropine toxicity.
- “Blind as a Bat” in the context of atropine toxicity refers to:
a) Permanent vision loss
b) Blurred vision
c) Night blindness
d) Color blindness
b) Blurred vision
Rationale: “Blind as a Bat” in atropine toxicity refers to the side effect of blurred vision.
- “Hot as a Hare” in atropine toxicity indicates:
a) Fever
b) Absence of sweating
c) Skin redness
d) Increased body temperature
b) Absence of sweating
Rationale: “Hot as a Hare” signifies the absence of sweating in atropine toxicity.
- Atropine’s effect on salivation is to:
a) Increase
b) Decrease
c) No change
d) Vary depending on dosage
b) Decrease
Rationale: Atropine decreases salivation as part of its muscarinic antagonist action.
- What makes succinylcholine unique among neuromuscular junction (NMJ) blockers?
a) It is the only non-depolarizing NMJ blocker
b) It has the longest duration of action
c) It is the only depolarizing NMJ blocker currently in use
d) It has no adverse drug reactions
c) It is the only depolarizing NMJ blocker currently in use
Rationale: Succinylcholine is unique because it is the only depolarizing neuromuscular junction blocker being used clinically.
- Succinylcholine is primarily used for:
a) Managing chronic pain
b) Reducing blood pressure
c) Inducing paralysis during surgery
d) Treating muscle spasms
c) Inducing paralysis during surgery
Rationale: Succinylcholine is commonly used to induce paralysis during surgery or facilitate mechanical ventilation.
- The typical duration of succinylcholine’s action is:
a) 1-2 minutes
b) 3-6 minutes
c) 10-15 minutes
d) Over 20 minutes
b) 3-6 minutes
Rationale: The effects of succinylcholine usually last between 3 to 6 minutes, making it suitable for short procedures.
- The most severe adverse drug reaction to succinylcholine is:
a) Hypotension
b) Malignant Hyperthermia
c) Allergic reactions
d) Nausea and vomiting
b) Malignant Hyperthermia
Rationale: Malignant Hyperthermia is the most common and severe adverse reaction to succinylcholine.
- The antidote used to treat Malignant Hyperthermia caused by succinylcholine is:
a) Epinephrine
b) Dantrolene
c) Atropine
d) Naloxone
b) Dantrolene
Rationale: Dantrolene is the antidote used to treat Malignant Hyperthermia, a severe reaction to succinylcholine.
- During the Phase I block of succinylcholine’s action, what occurs at the muscle cell?
a) Repolarization
b) Prolonged depolarization
c) Sensitization to acetylcholine
d) Inhibition of sodium channels
b) Prolonged depolarization
Rationale: In Phase I block, succinylcholine causes prolonged depolarization of the muscle cell, opening sodium channels.
- What is the effect of cholinesterase inhibitors during the Phase I block of succinylcholine?
a) They reverse the block
b) They potentiate the block
c) They have no effect
d) They shorten the duration of action
b) They potentiate the block
Rationale: During Phase I block of succinylcholine, cholinesterase inhibitors actually potentiate the effect, rather than reversing it.
- What characterizes the Phase II block in succinylcholine’s action?
a) The muscle cell remains depolarized
b) The muscle cell repolarizes but remains blocked
c) Immediate muscle contraction
d) Sensitization to acetylcholine
b) The muscle cell repolarizes but remains blocked
Rationale: In Phase II block, the muscle cell repolarizes but becomes desensitized to acetylcholine, preventing further action potential generation.
- What is the antidote for Phase II block caused by succinylcholine?
a) Dantrolene
b) Epinephrine
c) Neostigmine
d) Atropine
c) Neostigmine
Rationale: Neostigmine, a cholinesterase inhibitor, can be used to reverse the Phase II block caused by succinylcholine.
- Which clinical application is NOT a use for succinylcholine?
a) Treating hypertension
b) Facilitating mechanical ventilation
c) Acting as an adjuvant to general anesthesia
d) Inducing short-term paralysis
a) Treating hypertension
Rationale: Succinylcholine is not used for treating hypertension; it is used to induce paralysis during surgery and facilitate mechanical ventilation.
- What happens during succinylcholine-induced paralysis?
a) Voluntary muscle control is enhanced
b) There is a decrease in muscle tone
c) Rapid muscle contractions occur
d) Muscles are unable to contract
d) Muscles are unable to contract
Rationale: Succinylcholine causes paralysis by preventing muscle contraction through prolonged depolarization and subsequent desensitization.
- What is a key feature of succinylcholine’s mechanism of action?
a) It blocks the release of acetylcholine
b) It mimics acetylcholine at the NMJ
c) It inhibits cholinesterase
d) It activates nicotinic receptors
b) It mimics acetylcholine at the NMJ
Rationale: Succinylcholine mimics acetylcholine at the neuromuscular junction, leading to depolarization and paralysis.
- The reason succinylcholine is used as an adjuvant to general anesthesia is to:
a) Enhance pain relief
b) Reduce anxiety
c) Induce muscle relaxation
d) Prevent nausea
c) Induce muscle relaxation
Rationale: Succinylcholine is used alongside general anesthesia to induce muscle relaxation and facilitate surgical procedures.
- Which phase of succinylcholine’s action is reversible with cholinesterase inhibitors?
a) Phase I
b) Phase II
c) Both phases
d) Neither phase
b) Phase II
Rationale: Cholinesterase inhibitors like neostigmine can reverse the Phase II block of succinylcholine but not the Phase I block.
- The duration of succinylcholine’s effect is particularly suitable for:
a) Long surgical procedures
b) Short surgical procedures
c) Chronic pain management
d) Long-term mechanical ventilation
b) Short surgical procedures
Rationale: The short duration of action (3-6 minutes) makes succinylcholine suitable for short surgical procedures and rapid sequence intubation.
- Tubocurarine and Atracurium are examples of:
a) Depolarizing neuromuscular blockers
b) Nondepolarizing neuromuscular blockers
c) Cholinesterase inhibitors
d) Calcium channel blockers
b) Nondepolarizing neuromuscular blockers
Rationale: Tubocurarine and Atracurium are prominent nondepolarizing neuromuscular blockers used as muscle relaxants during surgery.
- The primary function of nondepolarizing neuromuscular blockers is to:
a) Increase muscle tone
b) Relax muscles during surgical procedures
c) Induce muscle contraction
d) Stimulate the central nervous system
b) Relax muscles during surgical procedures
Rationale: Nondepolarizing neuromuscular blockers are used to relax muscles in preparation for or during surgical procedures.
- The first muscles typically affected by nondepolarizing neuromuscular blockers are:
a) Limb muscles
b) Respiratory muscles
c) Muscles of the eyes and face
d) Abdominal muscles
c) Muscles of the eyes and face
Rationale: The initial effect of nondepolarizing neuromuscular blockers is usually observed in the muscles of the eyes and face.
- Which drug is used to reverse the effects of nondepolarizing neuromuscular blockers?
a) Dantrolene
b) Epinephrine
c) Neostigmine
d) Atropine
c) Neostigmine
Rationale: Neostigmine, a cholinesterase inhibitor, is commonly used to reverse the blockade caused by nondepolarizing neuromuscular blockers.
- Dantrolene is primarily used in the treatment of:
a) Parkinson’s disease
b) Malignant hyperthermia
c) Chronic pain
d) Hypertension
b) Malignant hyperthermia
Rationale: Dantrolene is used to treat malignant hyperthermia, particularly associated with the use of succinylcholine and halothane.
- The mechanism of action of dantrolene involves:
a) Stimulating calcium release in muscles
b) Preventing the release of calcium from the sarcoplasmic reticulum
c) Inhibiting acetylcholinesterase
d) Blocking sodium channels
b) Preventing the release of calcium from the sarcoplasmic reticulum
Rationale: Dantrolene works by inhibiting the release of calcium from the sarcoplasmic reticulum of skeletal muscle cells, reducing muscle contraction.
- Which condition is dantrolene also effective in treating?
a) Neuroleptic malignant syndrome
b) Glaucoma
c) Asthma
d) Diabetes
a) Neuroleptic malignant syndrome
Rationale: Dantrolene is effective in treating neuroleptic malignant syndrome, a severe reaction to antipsychotic drugs.