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Flashcards in Pharmaco5_Tuft Deck (23):
1

administration of ganglionic blocking agents will result in
• miosis
• diarrhea
• copious salivation
• orthoststic hypotension
• enhance activity of the parasympathetic nervous system

orthoststic hypotension

2

tachycardia in a patient administered with atropine or scopolamine results from?
• release of adrenal catecholamines
• blockade of vegus nerve activity
• blockade of the nicotinic cholinergic receptor
• stimulation of the alpha adrenergic receptor
• stimulation of the beta adrenergic receptor

blockade of vegus nerve activity - atropine and scopolamine are muscarinic cholinergic receptor blockers. Any sudden increase in heart rate usually stimulates baroreceptors to send a signal to the vagus nerve to stimulate the heart to slow it back down. This reflex is cholinergically mediated, and will be blocked by cholinergic blockers such as atropine. Even when given in the absence of higher than normal HR, atropine will block the normal cholinergic control over the heart, leaving the sympathetic system in charge with a resulting tachycardia

3

a paralyzing dose of succinylcholine initially alicits
• CNS stimulation
• CNS depression
• decreased salivation
• muscle fasiculation
• extrapyramidal reactions

muscle fasciculation (involuntary muscle contraction and relaxation which may be visible under the skin)

4

based on its known mechanism and sites of action, scopolamine should theoretically be useful in
• treatment of peptic ulcer
• providing euphoria and amnesia prior to surgery
• relieving bronchoconstriction
• relieving some of the symptoms of Parkinson's disease
• visualization of the retina

all of them

5

symptoms of poisoning by an organophosphate onsecticide include all of the following except
• skeletal muscle fasciculation
• excessive salivation
• bronchoconstriction
• hot, dry skin
• diarrhea

hot, dry skin

6

all of the following symptoms are associated with neostigmine poisoning except
• diarrhea
• salivation
• convulsion
• bronchiolar constriction
• skeletel muscle paralysis

skeletel muscle paralysis

7

symptoms of atropin poisoning in man include
• decreased intraocular pressure
• burning dry mouth
• nausea, vomiting and diarrhea
• hyperthermia
• orthostatic hypotension

• burning dry mouth
• hyperthermia
"the most likely sign is CNS excitation and tachycardia"

8

Disorientation, confusion, and hallucinations resulting from an overdose of scopolamine are most efficaciously treated by administering
a. atropine
b. levodopa
c. acetylcholine
d. physostigmine

physostigmine

9

the immediate cause of death from irreversible cholinesterase inhibitors is
• shock
• convulsion
• cardiac arrhythmia
• respiratory paralysis
• dehydration from vomiting and diarrhea

respiratory paralysis which results from the stimulation of nicotinic receptors at the neuromuscular junction resulting in paralysis of skeletal muscles

10

each of the following is a symptom of cholinergic crisis except
• bradycardia
• lacrimation
• vasoconstriction
• extreme salivation
• weakness of voluntary muscles

vasoconstriction

11

• alpha1 stimulation
• beta 1 stimulation
• beta 2 stimulation
• alpha1 block
• beta 1 block
• beta 2 block

• alpha1 stimulation: vasoconstriction, urinary retention, mydriasis
• beta 1 stimulation:increased heart rate
• beta 2 stimulation:brochodilation, vasodilation
• alpha1 block: vasodilation
• beta 1 block: decreased heart rate
• beta 2 block: bronchoconstriction

12

a mechanism for the antiadrenergic action of guanethidine is
• inhibition of dopa decarboxylase
• increased rate of metabolism of NE
• depletion of NE from the nerve terminals
• substitution for NE and subsequent action as a false transmitter
• uncoupling of the action potential from the NE release mechanism

uncoupling of the action potential from the NE release mechanism (inhibits the release of catecholamine)

13

which of the following statements most accurately describes the effectiveness of action of methyldopa?
• it causes marked cardiac slowing
• it directly relaxes vascular smooth muscle
• it causes rapid depletion of NE from adrenergic nerve terminals
• it causes formation of a false transmitter which is released at vascular smooth muscle
• it produces a false transmitter, the effect of which is primarily at central nuclei

it produces a false transmitter, the effect of which is primarily at central nuclei (thus decreasing sympathetic activity)

14

the mechanism of action of reserpine is to
• inhibit monoamine oxidase
• inhibit catechole-O-methyltransferase
• block the passage of the nerve action potential in the postgalglionic nerve fibers
• stabilize the axon terminal membrane thus preventing release of NE

stabilize the axon terminal membrane thus preventing release of NE (depletes NE by inhibiting reuptake)

15

amphetamine acts by
• promoting storage of the mediator
• causing a rapid release of the mediator
• causing a slow depletion of the mediator
• combining with a receptor substance on the effector cell
• interfering with the response of the receptor to the mediator

causing a rapid release of the mediator (it is a indirect acting drug like tyramine and ephedrine stimulating the release of stored NE)

16

which of the following characterizes the mechanism of action of levodopa?
• it acts through a direct cnticholinergic action
• it stimulates specific L-dopa receptors in basal ganglia
• it replenishes the otherwise deficient dopamine in patients with parkinsonism
• in increases concentrations of NE in the brain to counterbalance an otherwise overactive cholinergic system

it replenishes the otherwise deficient dopamine in patients with parkinsonism- levodopa is a sypathomimetic . carbidopa is given with levodopa to block dopa carboxylase activity

17

which of the following combinations of agents would be necessary to block the cardiovascular effects produced by the injection of a sympathomimetic drug?
a. atropine and prazosin
b. atropine and propranolol
c. prazosin and propranolol
d. phenoxybenzamine and curare
e. amphetamine and propranolol

prazosin and propranolol
a sympathomimetic drug is going to potentially activate both alpha and beta receptors, so you would need a pairing of drugs which blocks those receptors. Prazosin, an alpha-1 blocker, and propranolol, a non-specific beta-blocker, are the only pair that block both types sympathetic/adrenergic receptors. Atropine is a muscarinic blocker (anticholinergic), phenoxybenzamine is an alpha-blocker, but curare is a neuromuscular junction blocker. Amphetamine is a sympathomimetic drug, not a blocker or sympatholytic drug.

18

which of the following drugs competitively blocks the action of NE at beta-adrenergic receptors ?
• atropine
• naloxone
• propranolol
• phenotolamine
• hexamethonium

propranolol

19

pretreatment with reserpine prevents a response to which of the following agents?
• amphetamine
• epinephrine
• phenylephrine
• isoprotterenol
• NE

amphetamine - reserpine causes depletion of NE from storage sites, thus it can not be released by amphetamine. All of the others listed act postsynaptically

20

each of the following drugs is considered to be a direct acting catecholamine EXCEPT
• epinephrine
• amphetamine
• isoprotterenol
• NE

amphetamine

21

after pretreatment with phentolamine, intravenous administration of epinephrine should result in
• relaxation of bronchial muscle
• positive chronotropic and inotropic effects
• splanchnic vasoconstriction
• dilation of skeletal muscle vascular bed
• secretion of a mucoid viscous saliva

phentolamine is an alpha blocker, thus the epinephrine will stimulate beta receptors primarily with the listed effects mentioned
• relaxation of bronchial muscle
• positive chronotropic and inotropic effects
• dilation of skeletal muscle vascular bed

22

which of the following changes produced by intravenous administration of epinephrine results from stimulation of beta-adrenergic receptors?
• respiratory inhibition
• cardiac acceleration
• dilation of the pupil
• increased systolic pressure
• decreased diastolic pressure

• dilation of the pupil
• increased systolic pressure
• decreased diastolic pressure

23

which of the following in NOT an action of epinephrine when administered intravenously in high doses?
• increases liver glycogenolysis
• causes bronchiolar constriction
• produces a rise in blood pressure
• evokes extrasystoles in the heart
• produces restlessness and anxiety

causes bronchiolar constriction