910
P A R T 1 1
Drugs acting on the gastrointestinal system
■■
The GI protectant sucralfate forms a protective
coating over the eroded stomach lining to protect it
from acid and digestive enzymes to aid healing.
■■
Constipation is a common occurrence with this drug.
P
rostaglandin
Prostaglandins
are used to protect the stomach lining.
The prostaglandin available for this use is the synthetic
prostaglandin E
1
analogue misoprostol (
Cytotec
).
Therapeutic actions and indications
Prostaglandin E
1
inhibits gastric acid secretion and
increases bicarbonate and mucus production in the
stomach, thus protecting the stomach lining (see
Figure 57.1). Misoprostol is primarily used to prevent
NSAID-induced gastric ulcers in people who are at high
risk for complications from a gastric ulcer (e.g. elderly or
debilitated people, people with a past history of ulcer).
See Table 57.1 for more information and indications
about this drug.
Pharmacokinetics
Miosprostol is given orally. It is rapidly absorbed from
the GI tract, metabolised in the liver and excreted in
urine. Misoprostol crosses the placenta and enters breast
milk.
Contraindications and cautions
Misoprostol is contraindicated with allergy to any
part of the drug
to prevent hypersensitivity reactions.
KEY POINTS
■
■
Inspect the skin for colour and evidence of lesions
or rash
that might indicate adverse drug effects.
■
■
Assess the person’s neurological status, including
level of orientation, affect and reflexes,
to monitor
for CNS effects of the drug.
■
■
Examine the abdomen; auscultate bowel sounds
to evaluate GI motility
; evaluate bowel elimination
pattern or changes
that could suggest possible
adverse effects.
■
■
Assess mucous membrane status
to evaluate
potential problems with absorption.
■
■
Monitor the results of laboratory tests such as renal
function studies
to identify the need for possible
dose adjustments and toxic effects.
Implementation with rationale
■
■
Administer the drug on an empty stomach, 1 hour
before or 2 hours after meals and at bedtime,
to ensure the therapeutic effectiveness of the drug.
■
■
Monitor the person for GI pain,
and arrange to
administer antacids to relieve pain if needed.
■
■
Administer antacids or antibiotics, if ordered,
between doses of sucralfate, not within 30 minutes
of a sucralfate dose,
because sucralfate can
interfere with absorption of oral agents.
■
■
Provide comfort and safety measures if CNS effects
occur
to prevent injury.
■
■
Provide frequent mouth care, including sugarless
lozenges to suck,
to alleviate dry mouth
.
■
■
Ensure ready access to bathroom facilities
if diarrhoea occurs
; institute bowel training as
needed and provide small, frequent meals
if GI
effects are uncomfortable.
■
■
Offer support and encouragement
to help the
person cope with the disease and the drug regimen.
■
■
Provide thorough teaching, including the drug
name and prescribed dosage; schedule for
administration; importance of taking the drug
on an empty stomach; use of antacids if ordered
and the need to separate doses by at least 2 hours;
signs and symptoms of possible adverse effects and
measures to minimise or prevent their occurrence;
danger signs that need to be reported to the
healthcare provider immediately; safety measures,
such as avoiding driving and asking for help with
ambulation,
to minimise injury secondary to CNS
effects
; dietary measures such as small, frequent
meals
to minimise diarrhoea
; increased fluid and
fibre in the diet
to reduce the risk of constipation
;
small, frequent meals
to help with GI upset
;
comfort measures, such as mouth care and use
of sugarless lozenges,
to alleviate dry mouth
; the
importance of compliance with therapy
to achieve
the intended effects
; measures to help avoid adverse
effects; warning signs that may indicate problems;
and the need for periodic monitoring and
evaluation
to evaluate the effectiveness of therapy
,
enhance knowledge about therapy and promote
compliance.
Evaluation
■
■
Monitor the response to the drug (relief of GI
symptoms; healing of erosive GI lesions).
■
■
Monitor for adverse effects (GI effects, CNS
changes, dermatological effects).
■
■
Monitor the effectiveness of comfort and safety
measures and compliance with the regimen.
■
■
Evaluate the effectiveness of the teaching plan
(person can name drug and dosage and describe
the adverse effects to watch for, specific measures
to avoid them and measures to take to increase the
effectiveness of the drug).
