Anti Muscarinics

Question 1

semi synthetic tertiary antimuscurinic drug used for intestinal spasm

Answer 1

Dycycloverin ( dycyclomine)

Question 2

list all the centrally actin antimuscarinic drugs

Answer 2

Biperiden, benztropine, diphenhydramine (for more dramatic response), trihexyphenidyl

Question 3

drugs that selectively block M3 receptors and are used for the treatment of overactive bladder

Answer 3

Darifenacin, solifenacin, imidafenacin

Question 4

true or false. Tiotropium, oxytropium, aclidinium, and ipratropium are used for treating COPD and asthma

Answer 4

false. Aclidium is not used as treatment for asthma. Ipratropium, tiotropium, oxytropium- for asthma

Question 5

fuction of glycopyrolate

Answer 5

used for respiratory disorders

Question 6

Name the centrally acting antimuscarinic drugs

Answer 6

Biperiden, benztropine, diphenhydramine (for more dramatic response), trihexyphenidyl

Question 7

Name a tertiary antimuscarinic drug with the same function as trospium and homatropine methylbromide

Answer 7

Oxybutinin which is used for urinary incontenence. Trospium and Homatropine methylbromide are also used for urinatry incontinence

Question 8

what type of inhibition does and antimuscarinic drug exhibit?

Answer 8

COMPETITIVE INHIBITION. Reversible, equilibrium, surmountable - bind to receptor but no intrinsic activity of its own

Question 9

True or False. Heteroreceptors are found at the presynapticc muscarinic receptors.

Answer 9

False. At Presynaptic muscarinic receptors: autoreceptors | At sympathetic nerve fibers: heteroreceptors

Question 10

Explain the mechanism of action upon blocking presynaptic M2 receptors

Answer 10

Blockade of M2 can augment transmitter release. Presynaptic M2 modulates release of Ach - decreases of Ach - decrease Ach effect. With an antimuscarinic drug blocking the M2 receptor, there is an increase of Ach release.

Question 11

Explain the paradoxical response occuring upon blocking the M3 receptor

Answer 11

antimuscarinic blocks M3 receptors, which result to brochodilation. However, M2 receptor blockade (wherein its function as a modulator of Ach is reduced - inc Ach) can counteract the effect of blocking M3. Blocking M3 results to a paradoxical response of increased levels of Ach - bronchoconstiction

Question 12

name 4 drugs that possess inverse agonism

Answer 12

Atropine, ipratropium glycopyrrolate, trihexyphenidyl

Question 13

Between atropine and scopolamine, which drug can easily penetrate the blood brain barrier?

Answer 13

scopolamine has a greter permeation across BBB than atropin

Question 14

compare Atropine and Scopolamine in terms of their predilection

Answer 14

Atropine - heart, GI,bronsial smooth muscle. Scopolamine: iris sphincter, ciliary muscle, exocrine glands

Question 15

which drug has a prominent central effects at therapeutic dose? (atropine/scopolamine)

Answer 15

Scolpolamine

Question 16

true or false. Scopolamine exhibits both depression and excitation central effects at a therapeutic dose.

Answer 16

True. Excitation is occasionally in presence of severe pain

Question 17

side effect of using scopolamine as an antiemetic

Answer 17

dry mouth

Question 18

Why use first generation H1 receptor blockers as antiemetic?

Answer 18

first genereation H1 receptor blockers have antimuscarinic/atropine like effect

Question 19

Antimuscarnic drugs that are used for parkinsons disease.

Answer 19

centrally acting/ tertiary antimuscarinic drugs ( biperiden, benztropine, diphenhydramine, trihexyphenidyl)

Question 20

why are the ventricle less affected by the effects of the antimuscarinic drugs?

Answer 20

ventricles are less affected due to less vagal parasympathetic control

Question 21

explain how atropine causes a paradoxical bradycardia at very low dosed given by slow IV.

Answer 21

There is a blockade of your prejunctional M1 receptors on the vagal postganglionic fibers that limit Ach release in SA node - Removal of autoinhibition - increased Ach release - bradycardia (but once peripheral effects from atropine takes place, tachycardia occurs)

Question 22

effects of atropine to the circulation when given alone in clinical doses

Answer 22

Atropin counteracts peripheral vasodilation and sharp fall in bp induced by choline esters. M3 in vascular endothelium are not innervated by the parasympathetic system. However, M3 responds to muscarinic agonist. By blocking M3 heteroreceptors antimuscarinic can then counteract vasodilation effects - vasoconstriction

Question 23

effects of atropine to the circulation when given alone in toxic doses

Answer 23

atropine flush

Question 24

effects of large doses of atropine to the gastrointestinal tract

Answer 24

completely abolish Ach on GI motility and secretion only; Decrease amplitude and frequency of propulsive movements means more relaxed walls, Basal secretion is blocked more effectively than that stimulated by food, alcohol, or nicotine

Question 25

selective M1 antimuscarinic drugs that selectively inhibit gastric acid secretion only

Answer 25

pirizepine and telenzepine

Question 26

which is more selective in blocking M1 receptors? (Telenzepine/pirenzepine)

Answer 26

Telenzepine

Question 27

why is diphenoxylate more effective when taken with atropine in treating traveller's diarrhea?

Answer 27

diphynoxylate can cause dryness of mouth. To prevent this, very low dose of atropin is take.

Question 28

True or false. Effects of endogenous muscarinics are more effectively blocked than those exogenously administered muscarinics.

Answer 28

False. Exogenously administered muscarinic stimulants are more effectively blocked than those following vagal impulsive activity/ Parasympathetic nerve activity (edogenous ach)

Question 29

Usage of dicyclomine

Answer 29

reduces intestinal spasm

Question 30

nonselective drugs for treating overactive bladder/OAB

Answer 30

Tolterodine, oxybutynin, trospium, propiverine

Question 31

selective M3 blockers that are effective in treating overactive bladder

Answer 31

Solifenacin, Darifenacin, imidafenacin

Question 32

compare effects of muscarinic agonist and antimuscarinic to the ciliary muscles.

Answer 32

muscarinic agonist: cyclopasm; antimuscarinis: cycloplegia

Question 33

effects of antimuscarinis to the ocular system

Answer 33

mydriasis, cycloplegia, sandy eyes

Question 34

true or false. Antimuscarinics dilates the eye by acting on the radial muscles

Answer 34

False. Antimuscarinics do not stimulate redial muscles

Question 35

explain how antimuscarinics cause mydriasis.

Answer 35

recall that Blocking the more dominant division (parasympathetic) - see more effect of the sympathetic system (submissive division. Antimuscarinic inhibits the parasymathetic effect of colinergics (pupillary constriction) making it possible for the sympathetic effect (vasodilation) to be observed

Question 36

which of the following drugs can be used for fundoscopy requiring cycloplegic effects? (Tropicamide/cyclopentylate/Scopolamine/atopine)

Answer 36

atropine

Question 37

arrange the following antimuscarinics bsased on their duration of effect in decreasing order. scopolamine, atropine, cyclopentylate, tropicamide, homatropine,

Answer 37

Tropicamide: 15-60 mins | Cyclopentylate: 3-6 hrs | Homatropine: 12-24 hrs | Scopolamine: 3-7 days | Atropine: 5-6 days blocked more effectively 

Question 38

effect of atropine to the respiratory tract

Answer 38

brochodilation. However, it decreases mucociliary clearance and can form a mucous plug (can be a site for bacterial proliferation)

Question 39

what is the advantage of using Ipratropium, oxitropium, and tiotropium over atropine?

Answer 39

Less inhibitory effect on mucociliary clearance as compared to atropine. sideeffect: dry mouth

Question 40

how does ipratropium counteract the blockade of m3 receptor-mediated brochoconstriction

Answer 40

Ipratropium ounteracts blockade of M3 mediated bronchoconstriction due to removal of autoinhibition by blockin M2 receptor. Ipratropium blocks all muscarinic receptors including presynaptic M2 leading to removal autoinhibition - increase Ach - bronchodilation.

Question 41

compare and contrast therapeutic usage of tiotropim and aclidinium.

Answer 41

tiotropium: used for both COPD and asthma; aclidinium: only used for COPD and not for asthma

Question 42

effect of atropine to the exocrine gland

Answer 42

xerostomia, anhydrosis, atropine fever (due to the suppression of thermoregulatory sweatin

Question 43

effects of scopolamine to the CNS

Answer 43

CNS Depressant (drowsiness, amnesia, fatigue, dremless sleep, decrease REM, suphoria) and anti-emetic

Question 44

centrally acting antimuscarinic drugs

Answer 44

Benztropine, biperiden, trihexyphenidyl, procyclidine, diphenhydramine

Question 45

toxic effects of antimuscarinics

Answer 45

xerostomia, cycloplegia, atropine flush, atropine fever, cns excitation

Question 46

treatment for atropine taken orally

Answer 46

gastric lavage with activated charcoal slurry without delay

Question 47

drugs used for atropine poisoning that can also cross BBB

Answer 47

physostigmine

Question 48

Antimuscarinic that is given through IV for sedation and seizures

Answer 48

benzodiazepines

Question 49

drugs used for treating antimuscarinic poisoining due to quarternary compounds

Answer 49

neostigmine and sympathomimetic

Question 50

list 5 contraindication of antimuscarinics

Answer 50

narrow angle glaucoma, benign prostativ hyperplasia, bstructive conditions: urinary tract, GIT, Gastric ulcer, intestinal atony

Question 51

when can anti-muscarinic be used for opthalmologic diagnosis?

Answer 51

if cycloplegic or prolonged action is required in fundoscopy

Question 52

what drugs can be used for opthalmologic diagnosis that only require myadriasis?

Answer 52

sympathomimetic drugs and alpha adrenoreceptor stimulant (phenylephrine)

Question 53

List some opthalmologic diseases wherein antimuscarinics are used for treatment.

Answer 53

anterior uveitis, acute irits, iridocyclitis, keratitis, prevent synechia formation

Question 54

List 4 gastrointestinal disorders that can be treated by antimuscarinics

Answer 54

acid peptic disease, common traveller's diarrhea, intestinal spasm, reflux esophagitis

Question 55

drug used for traveller's diarrhea that does not have diphynolate

Answer 55

lomotil

Question 56

antimuscarinic drug that enhances the gastric emptying time and prevents reflux by increasing the lower esophageal pressure

Answer 56

metoclopramide

Question 57

antimuscarinics used for reflux esophagitis

Answer 57

metoclopramide and betanechol preferred drug

Question 58

antimuscarinic drugs used for acid peptic disease

Answer 58

pirizepine and telenzepine

Question 59

List the therapeutic uses of antimuscarinics in the genitourinary tract

Answer 59

urolithiasis, enuresis in childre, urniary incontinence, overactive bladder

Question 60

antimuscarinic drug used to decrease urinary spasm in ureter

Answer 60

hyoscine

Question 61

used to relieve bladder spasm after urologic surgery and in reducing involuntary voiding in patinets with neurologic disease

Answer 61

oxybutinin

Question 62

antimuscarinic nonselective antagonists with greater selectivity for M3 receptors than oxybutinin or trospium

Answer 62

darifenacin and solifenacin

Question 63

a tricyclic antidepressant drugs that is used to reduce incontinence in institutionalized elderly patients

Answer 63

impramine

Question 64

antimuscarinic drug used for COPD and has a longer bronchodilation action thatn ipratropium

Answer 64

tiotropium.

Question 65

antimuscarinic drug given to patients with mycetism

Answer 65

atropine