Transcript ANSCholinergicBlocki..

Cholinergic – Blocking Drugs
Cholinergic-Blocking Drugs
 Describe the cholinergic-blocking drug effects on
major body systems.
 Discuss the nursing process in the care of patients
receiving cholinergic-blocking drugs for
cardiovascular, respiratory, gastrointestinal, and
genitourinary system problems.
Cholinergic-Blocking Drugs
Mechanism of Action
Drugs that block or inhibit the actions of acetylcholine (ACh)
in the parasympathetic nervous system (PSNS)
 anticholinergics
 Compete with Ach & block ACh at the muscarinic receptors
in the PSNS
 ACh is unable to bind to the receptor site and cause a
cholinergic effect
Once these drugs bind to receptors, they inhibit
nerve transmission at these receptors
Cholinergic-Blocking Drugs
Cholinergic-Blocking Drugs
Chemical Class
Natural
Synthetic/
Semisynthetic
atropine
benztropine (Cogentin)
Belladonna dicyclomine (Bentyl)
glycopyrrolate
Robinul)
Hyoscyamine homatropine
ipratropium
Scopolamine isopropamide
methscopolamine
oxybutynin (Ditropan) propantheline
tolterodine (Detrol)
solifenacin (Vesicare)
Cholinergic-Blocking Drugs
Drugs
 Atropine – preop; bradycardia;
 Dicyclomine (Bentyl) – irritable bowel syndrome
 glycopyrrolate (Robinul) – intraop to control secretions;
PUD (peptic ulcer disease), reversal of neuromuscular
blockers
 Oxybutynin (Ditropan) – antispasmodic for neurogenic
bladder; overactive bladder; spinal cord injury
 Scopolamine (Transderm-Scop) – control of secretions;
motion sickness
 Tolterodine (Detrol) – overactive bladder
Cholinergic-Blocking Drugs
Drug Effects
 Cardiovascular
 Small doses: decrease heart rate
 Large doses: increase heart rate
 CNS
 Small doses: decrease muscle rigidity
and tremors
 Large doses: drowsiness, disorientation, hallucinations
 Respiratory
 Decreased bronchial secretions
 Dilated bronchial airways
Cholinergic-Blocking Drugs
Drug Effects
 Eye
 Dilated pupils (mydriasis)
 Decreased accommodation due to paralysis
of ciliary muscles (cycloplegia)
 Gastrointestinal
 Relax smooth muscle tone of GI tract
 Decrease intestinal and gastric secretions
 Decrease motility and peristalsis
Cholinergic-Blocking Drugs
Drug Effects
 Genitourinary
 Relaxed detrusor muscle
 Increased constriction of internal sphincter
 Result: urinary retention
 Glandular
 Decreased bronchial secretions, salivation, sweating
Cholinergic-Blocking Drugs
Indications - CNS
 To decrease muscle rigidity and muscle tremors
 Parkinson’s disease
 Drug-induced extrapyramidal reactions
Cholinergic-Blocking Drugs
Indications - Cardiovascular
Affect the heart’s conduction system
 Low doses: slow the heart rate
 Appropiate doses: block inhibitory vagal effects on the SA
and AV node pacemaker cells
 Intended Effect: increased heart rate
 Uses:
 Diagnosis of sinus node dysfunction
 Symptomatic second-degree heart block
 Severe sinus bradycardia with hemodynamic
compromise (advanced life support)
Cholinergic-Blocking Drugs
Indications – Respiratory
 Blocking the cholinergic stimulation of the PSNS
allows unopposed action of the SNS
 Results
 Decreased secretions from nose, mouth, pharynx,
bronchi
 Relaxed smooth muscles in bronchi and bronchioles

Bronchodilation
 Decreased airway resistance
Cholinergic-Blocking Drugs
Indications - Respiratory
Respiratory drugs are used to treat:
 Exercise-induced bronchospasms
 Chronic bronchitis
 Asthma
 Chronic obstructive pulmonary disease
Cholinergic-Blocking Drugs
Indications - Gastrointestinal
 PSNS controls gastric secretions and smooth muscles that
produce gastric motility
 Blockade of PSNS results in:
 Decreased secretions
 Relaxation of smooth muscle
 Decreased GI motility and peristalsis
Gastrointestinal drugs are used to treat:
 Irritable bowel disease
 GI hypersecretory states
 Acute pancreatitis (reduces gastric and pancreatic secretions)
Cholinergic-Blocking Drugs
Indications - Genitourinary
 Reflex neurogenic bladder
 Incontinence
Cholinergic-Blocking Drugs
Other Indications
Preoperatively
to reduce salivary secretions
Cholinergic-Blocking Drugs
Adverse Effects
Body System
Adverse Effects
Cardiovascular
Increased heart rate, dysrhythmias
CNS
Excitation, restlessness, irritability,
disorientation, hallucinations, delirium
Eye
Dilated pupils, decreased visual accommodation,
increased intraocular pressure
Gastrointestinal
Decreased salivation, decreased gastric
secretions, decreased motility
Genitourinary
Urinary retention
Glandular
Decreased sweating
Respiratory
Decreased bronchial secretions
Cholinergic-Blocking Drugs
Interactions
 Antihistamines
 phenothiazines
 tricyclic antidepressants
 MAOIs
 When given with cholinergic blocking drugs, cause
additive effects, resulting in increased effects
Cholinergic-Blocking Drugs
Nursing Implications
 These drugs will block the action of ACh in the PSNS
 Assess for allergies, presence of BPH, glaucoma,




tachycardia, MI, HF, hiatal hernia, and GI or GU
obstruction
Perform baseline assessment of vital signs and systems
overview
Medications should be taken exactly as prescribed to
have the maximum therapeutic effect
Overdosing can cause life-threatening problems
Blurred vision may cause problems with driving or
operating machinery
Cholinergic-Blocking Drugs
Nursing Implications
 Patients may experience sensitivity to light – sun glasses
 When giving ophthalmic solutions, apply pressure to
the inner canthus to prevent systemic absorption
 Dry mouth may occur: chewing gum, frequent mouth care,
and hard candy
 Check with physician before taking any other medication,
including OTC medications
 Antidote for atropine overdose is physostigmine
Cholinergic-Blocking Drugs
Nursing Implications – Patient Ed
 Anticholinergics taken by the elderly patient may lead
to higher risk for heatstroke due to effects on heatregulating mechanisms
 Teach patients to limit physical exertion and avoid
high temperatures and strenuous exercise
 Emphasize the importance of adequate fluid and salt
intake
Cholinergic-Blocking Drugs
Patient Education
Patients should report the following to their
physician:
 Urinary hesitancy and/or retention
 Constipation
 Palpitations
 Tremors, confusion, sedation or amnesia,
 Excessive dry mouth
 especially if pt. chronic lung infections or disease
 Fever
Cholinergic-Blocking Drugs
Nursing Implications
Monitor for therapeutic effects
 For patients with Parkinson’s disease: fewer
tremors and decreased salivation and drooling
 For urologic problems: improved urinary patterns,
less hypermotility, increased time between voiding
Monitor for adverse effects