902
P A R T 1 1
Drugs acting on the gastrointestinal system
CRITICAL THINKING SCENARIO
Histamine-2 antagonists
THE SITUATION
W.T., a 48-year-old travelling salesman, had experienced
increasing epigastric discomfort during a 7-month period.
When he finally sought medical care, the diagnosis was
a peptic ulcer. He began taking Mylanta for relief of his
immediate discomfort, as well as ranitidine (
Tagamet
),
150 mg b.i.d. W.T. was referred to the nurse for teaching
and given an appointment for a follow-up visit in
3 weeks.
CRITICAL THINKING
Think about the physiology of duodenal ulcers and the various
factors that can contribute to aggravating the problem.
What teaching points should be covered with this
person regarding diet, stress factors, and use of alcohol
and tobacco?
What adverse effects of the drugs should this person be
aware of?
What lifestyle changes may be necessary to ensure ulcer
healing, and how can W.T. be assisted in making these
changes fit into the demands of his job?
DISCUSSION
Further examination indicated that W.T. is a healthy man
except for the ulcer. He admits to smoking cigarettes,
drinking alcohol regularly at business lunches and dinners,
and eating a great deal of fast food and drinking a lot
of coffee when he is on the road. He states that his job
has become increasingly stressful as the economy has
worsened. Because he is basically healthy and does not
seek medical care unless very uncomfortable (7 months
of pain), he may find it difficult to comply with his drug
therapy and any suggested lifestyle changes.
W.T. needs education, which for purposes of building
trust, should preferably be with the same nurse. The
instruction should include information on duodenal ulcer
disease; ways to decrease acid production (such as avoiding
cigarettes, acid-stimulating foods, alcohol and caffeine); and
ways to improve the protective mucus layer of the stomach
by decreasing stress and anxiety-causing situations. In
addition, spacing of the ranitidine and antacid doses should
be stressed. Ranitidine should be taken 1 hour before or
2 hours after any antacids because they can interfere with
the absorption of ranitidine and the person may not receive
a therapeutic dose. W.T. should be encouraged to avoid
OTC medications and self-medication because several of
these products contain ingredients that could aggravate
his ulcer or interfere with the effectiveness of the drugs that
have been prescribed. W.T. should be encouraged to return
for regular medical evaluation of his drug therapy and his
underlying condition.
Finally, W.T. should feel that he has some control over
his situation. Because he does not routinely seek medical
care, he may be more comfortable with a medical regimen
that he has participated in planning. Allow him to suggest
ways to decrease stress, ways to cut down on smoking or
the use of alcohol without interfering with the demands of
his job, and the best times to take the drugs in his schedule.
He will learn in time which foods and situations irritate his
condition. However, research has not shown that bland
or restrictive diets are particularly effective in decreasing
ulcer pain or spread, and they may actually increase anxiety.
W.T. should be encouraged to jot down the situations or
times of day that seem to cause him the most problems.
This information can help to provide a guide for adjusting
lifestyle and/or dietary patterns to aid ulcer healing and
prevent further development of ulcers.
CARE GUIDE FOR W.T.: HISTAMINE-2
ANTAGONISTS
Assessment: History and examination
Assess W.T.’s health history for allergies to any of these
drugs, renal or hepatic failure, and other drugs being
taken, such as antimetabolites, alkylating agents, oral
anticoagulants, phenytoin, beta-blockers, alcohol,
quinidine, lignocaine, theophylline, benzodiazepines,
nifedipine, tricyclic antidepressants (TCAs) and
carbamazepine.
Focus the physical examination on the following areas:
Neurological: orientation, affect
Skin: colour, lesions
Cardiovascular: pulse, cardiac auscultation
GI: liver evaluation
Laboratory tests: full blood count, liver, renal function tests
Implementation
Administer with meals and at bedtime.
Provide comfort and safety measures: analgesics, access to
bathroom, safety precautions.
Arrange for decreased dose in renal/hepatic disease.
Provide support and reassurance to deal with drug effects
and lifestyle changes.
Provide teaching regarding drug name, dosage, adverse
effects, precautions and warnings to report.
Evaluation
Evaluate drug effects: relief of GI symptoms, ulcer healing,
prevention of ulcer progression.
Monitor for adverse effects: headache, dizziness, insomnia,
gynaecomastia, arrhythmias, GI alterations.
