C H A P T E R 3 3
Anticholinergic agents
507
■■
Atropine is the most commonly used anticholinergic
drug. It is indicated for a wide variety of conditions
and is available in oral, parenteral and topical forms.
■■
People receiving anticholinergic drugs must be
monitored for dry mouth, difficulty swallowing,
constipation, urinary retention, tachycardia, pupil
dilation and photophobia, cycloplegia and blurring of
vision, and heat intolerance caused by a decrease in
sweating.
KEY POINTS
Care considerations for
people receiving anticholinergic agents
Assessment: History and examination
■
■
Assess for contraindications or cautions: any known
allergies to these drugs
to avoid hypersensitivity
reactions
; glaucoma; stenosing peptic ulcer,
intestinal atony, paralytic ileus, GI obstruction,
severe ulcerative colitis and toxic megacolon;
prostatic hypertrophy and bladder obstruction;
cardiac arrhythmias, tachycardia and myocardial
ischaemia,
all of which could be exacerbated
by parasympathetic blockade
; impaired liver or
kidney function,
which could alter the metabolism
and excretion of the drug
; myasthenia gravis,
which could worsen with further blocking of
the cholinergic receptors
; pregnancy
because
of the potential for adverse effects on the fetus
;
breastfeeding
because of possible suppression of
breastfeeding
; hypertension
because of the possible
additive hypertensive effects
; and muscle spasticity
and brain damage,
which could be exacerbated by
cholinergic blockade.
See the Critical thinking scenario to learn more
about care for the person who has heart disease and
is taking anticholinergic drugs.
■
■
Perform a physical assessment, including a review of
all body systems,
to establish baseline status before
beginning therapy, determine drug effectiveness and
evaluate for any potential adverse effects.
■
■
Assess neurological status, including level of
orientation, affect, reflexes and papillary response,
to evaluate any CNS effects.
■
■
Monitor vital signs and cardiopulmonary status,
including pulse, blood pressure, heart rate and
heart sounds; auscultate lung sounds. Obtain an
electrocardiogram if ordered
to identify changes
in heart rate or rhythm.
■
■
Assess abdomen; auscultate bowel sounds. Evaluate
bowel and bladder patterns; monitor urinary
output; palpate bladder for possible distension
to evaluate for GI and GU adverse effects.
■
■
Monitor the results of laboratory tests, including
renal function studies,
to determine need for
possible dose adjustment and to identify potential
toxicity.
Implementation with rationale
■
■
Ensure proper administration of the drug
to ensure
effective use and decrease the risk of adverse effects
(see Focus on safe medication administration).
■
■
Provide comfort measures
to help the person
tolerate drug effects
: sugarless lozenges to suck
and frequent mouth care
to alleviate problems
associated with dry mouth
; lighting control
to alleviate photophobia
; small and frequent
meals
to alleviate GI discomfort
; bowel
program, including a high-fibre diet,
to alleviate
constipation
; safety precautions, such as side rails
if appropriate, assistance with ambulation and
advice to avoid driving or operating hazardous
machinery
to prevent injury if CNS effects are
severe
; analgesics
to relieve pain if headaches
occur
; voiding before taking medication
if urinary
retention is a problem
(commonly occurs with
benign prostatic hyperplasia); and encouraging
fluid intake and monitoring heat exposure
because
the ability to sweat will be reduced.
■
■
Monitor response closely, including blood pressure,
electrocardiogram, urine output and cardiac output,
for changes that may indicate a need to adjust dose
to ensure benefit with the least amount of toxicity.
■
■
Offer support and encouragement
to help the
person deal with the drug regimen.
■
■
Provide thorough teaching about drug name,
dosage and schedule for administration; proper
technique for topical application, if appropriate
(see Focus on safe medication administration);
measures to minimise or prevent adverse effects;
safety measures such as avoiding driving, avoiding
operating hazardous machinery, staying hydrated
and monitoring exposure to heat; dietary
recommendations if appropriate; warning signs
of problems and the need to report these; and
importance of follow-up monitoring and evaluation.
Evaluation
■
■
Monitor response to the drug (improvement in
disorder being treated).
■
■
Monitor for adverse effects (cardiovascular changes,
GI problems, CNS effects, urinary hesitancy and
retention, pupil dilation and photophobia, decrease
in sweating and heat intolerance).
■
■
Evaluate the effectiveness of the teaching plan
(person can name drug, dosage, adverse effects
to watch for and specific measures to avoid them,
proper administration of ophthalmic drugs).
■
■
Monitor the effectiveness of comfort measures and
compliance with the regimen.
