Anticholinergics Flashcards
brand name of atropine
atropine
how is atropine supplied
- 4 mg/mL (vial)
0. 1 mg/mL (1mg ER injector)
classification of atropine
tertiary amine
alkaloid of belladonna plant
MOA of atropine
Competitive antagonist
Combines reversibly with muscarinic cholinergic receptors to block the action of Ach at parasympathetic postganglionic sites.
*crosses BBB easilty
*combines to receptor without leading to the cell membrane permeability, inhibition of adenylate cyclase and alteration in calcium response that would normally lead to a cholinergic response in the presence of Ach.
Little effect at nicotinic cholinergic receptos
Weak analgesic action
M1 receptor function
M1- CNS stomach
M2 receptor function
M2- airway smooth muscle and the heart
M3 receptor function
M3- CNS, airway smooth muscle, glandular tissues and vascular endothelial cells.
M4 receptor function
M4- CNS
M5 receptor function
M5- CNS
uses of atropine
preopmedication to inhibit salivation and secretions
treatment of symptomatic sinus bradycardia
AV block
antidote for anticholinesterase poisoning, organophosphate insecticides
decrease side effects of anticholinesterases (edrophonium and neostigmine)
ophthalmic- mydrasis and cycloplegia for examination
dose of atropine for neuromuscular blockage reversal
IV 25-30 mcg/kg 30-60 seconds before neostigmine or 7-10 mcg/kg 30-60 seconds before edrophonium
is atropine effective with heart transplant patients for increasing the HR
NO- bradycardia may unresponsive
dose of atropine for treating bradycardia
IV 0.5 mg q 3-5 minutes
not to exceed a total of 3 mg
max dose of atropine for bradycardia
3 mg or 0.4 mg/kg
dose of atropine for salivation inhibition preanesthesia
IM IV Subq
0.4-0.6 mg 30-60 minutes preop
q4-6 hours
what effect can doses of less than 0.5 mg of atropine have on the bradycardic patient
paradoxical bradycardia
what is given along with atropine during organophosphate poisoning to decrease secretions
pralidoxime
cholinesterase reactivator
what actions does atropine reverse?
muscarinic but NOT nicotinic effects of organophosphate poisoning
onset of atropine
about 1 minute
peak of atropine
?
duration of atropine
30-60 minutes IV
2-4 hours IM
metabolism of atropine
hepatic via enzymatic hydrolysis to inactive metabolites
effects may be prolonged with severe hepatic impairment
half life of atropine
2-3 hours
much longer in children
elimination of atropine
renal (30-50%)
unchanged drug and metabolites
adverse CV effects of atropine
Cardiac arrhythmias, flushing, hypotension, palpitations, tachycardia.
(not for 2degree type 2 or 3degree AV block). Caution with HF, CAD, tachyarrhythmias, → MI
low doses can cause transit decrease in HR mediated through an unkown mech
Larger doses increase HR by blocking bagal effects on M2 receptors on the SA node. High doses of atropine cause skin vasodilation.
adverse CNS effects of atropine
ataxia, coma, delirium, disorientation, dizziness, drowseiness, excitement, hallucination, HA, insomnia, nervousness (treat with physostigmeine)
adverse derm effects of atropine
anhydrosis, scarlatiniform rash, skin rash, urticarial,
adverse GI effects of atropine
decreased motility from esophagus to colon,
Ageusia loss of taste,
bloating constipation, delayed gastric emptying, nausea, paralytic ileus, vomiting, zerostomia,
LES sphincter relaxation, decreased barrier pressure and an increased in incidence of reflux from stomach to esophagus
adverse GU effects of atropine
urinary hesitancy
urinary retention
NMS adverse effects of atropine
laryngospasm
weakness
adverse respiratory effects of atropine
decreased volume of secretions from the nose, mouth, pharynx, and bronchi, decreases airway resistance via relaxation of bronchi and bronchiolar smooth muscle.
contraindications of atropine
Pts with obstructive uropathy
Contraindicated in patients with prostatic hypertrophy
Pts with pyloric stenosis
Avoid: hiatal hernia, paralytic ileus, intestinal atony of elderly patient, severe ulcerative colitis, toxic megacolon
Expected with atropinization:
flushing, mydriasis, tachycardia, dyness of mouth/nose
brand name of glycopyrolate
Robinul
how is glycopyrolate supplied
0.2 mg/mL
classification of glycopyrolate
quaternary ammonium compound
does glycopyrolate cross the BBB
no
more potent than atropine but lacks CNS activity because of poor penetration of the BBB
MOA of glycopyrolate
competitive antagonist
combines reversibly with muscarinic cholinergic receptors to block the action of Ach at parasympathetic postganglionic sites
combines to receptor without leading to the cell membrane permeability
inhibits adenylate cyclase
alters calcium response that normally leads to a cholinergic response in the presence of Ach
little to no effects at nicotinic cholincergic receptors
uses of glycopyrolate
Adjunct with acetylcholinesterase inhibitors = ANTAGONIZE effect of Ach at muscarinic receptors
Inhibit salivation and excessive secretions
intraopperatively to counteract drug induced BRADYARRHTHMIAS
COPD/ chronic bronchitis and emphysema maintenance
dose of glycopyrolate for NBM reversal
- 05-0.15 mg/kg
0. 2 mg for each 1 mg of neostigmine or 5 mg of pyridostigmine
dose of glycopyrolate for reduction of secretions
preoperatively IM 4 mcg/kg
intra-op IV 0.1 mg repeated as needed 2-3 minutes intervals
when do you give glycopyrolate for reduction of secretions preoperatively
30-60 minutes before procedure
onset of glycopyrolate
2-3 minutes
peak of glycopyrolate
5 min
half-life of glycopyrolate
1.25 hours
variable with kids
metabolism of glycopyrolate
hepatic minimal renal 80%
elimination of glycopyrolate
85% renal- unchanged drug
adverse effects of glycopyrolate
Cholinergic side effects
same as atropine
except LOW CNS SE d/t poor penetration of BBB
typical dose for glycopyrolate
0.2 mg intraoperatively for bradycardia
what is glycopyrolate incompatible with
LR
is glycopyrolate safe with glaucoma patients?
least mydriatic
dose for bradycardia does not cause adverse effects with these patients.
brand name of scopalamine
transderm-Scop
how is scopolamine supplied
1.5 mg in 72 hour patch
classification of scopalamine
tertiary amine
alkaloid of belladonna plant
properties of scopolamine on BBB
easily penetrates BBB
lipophilic
MOA of scopalamine
Competitive antagonist blocking action of acetylcholine at parasynaptic sites at cholinergic (postganglionic) muscarinic receptors in smooth muscle (GI, GI, Heart), secretory glands (salivation), and CNS
Increases CO
Dries secretions
No nicotinic effects
uses of scopolamine transdermal
N/V
motion sickness and recovery from ages and surgery
uses of scopolamine injection
preoperative medication to produce amnesia, sedation, tranquilization, antiemetic effects, decrease salivary and respiratory secretion
dose of scopolamine transdermal patch
5mcg/hr for 72 hours
1 patch hairless location
4 hours before surgery/night before
1 hour before cesarean section
dose of scopalopmine subq
antiemetic
0.6- 1 mg
dose of scopolamine IM IV subQ
0.6 mg 3-4 x daily
onset of scopolamine oral,
Oral IM 0.5-1 hour
transdermal
Transdermal 6-8 hours
peak of scopalomine
20-60 minutes
half life of scopalamine
2-3 hours
metabolism of scopalomine
primarily hepatic
elimination of scopolamine
1 % unchanged in urine
adverse effects of scopolamine CV
Cardiac arrhythmias, flushing, orthostatic hypotension, palpitations, tachycardia.
AE of scopolamine CNS
Acute toxic psychosis (rare), agitation (rare), ataxia, confusion ,delusion (rare), disorientation, dizziness (rare), drowsiness, fatigue, hallucinations, HA, irritability, loss of memory, paranoid, restless
Sedation: 100 X more potent than atropine at inhibiting the RAS- enhances sedative s/e of opiods or BZDs signinficantly less sedation with patch vs IV
derm AE or scopalamine
: skin eruptions, dry skin, dyshidrosis, erythema, pruritus, rash, urticarial,
endocrine AE of scopalomine
thirst
can scopolamine be given to a pregnant woman
class C crosses placenta may cause respiratory depression neonatal hemorrhange 1 hour before c-section to reduce risk
scopolamine is the most effective…
antisalagogue
at preventing motion sickness
most sedative also
scopolamine has the least affect on…
heart rate of the 3 anticholinergics
contraindications with scopalamine
Avoid with obstructive uropathy
Prostatic hypertrophy
Narrow angle glaucoma
Pyloric stenosis
GU,GI AE with scopolamine
GU: constipation, diarrhea, dry throat, dysphagia, n/v xerostomia,
GI dysuria, urinary retention
ocular AE with scopalomine
Ocular: impair accommodation, blurred vision, conjunctival infection ,cycloplegia, dryness, glaucoma,
respiratory AE with scopolamine
Resp: dry nose, dyspnea
other AE with scopolamine
Misc, anaphylaxis, shock, angio-edema, diaphoresis, hypersensitivity, heat intolerance