936
P A R T 1 1
Drugs acting on the gastrointestinal system
combination should be avoided. There is a decrease
in effectiveness of warfarin if they are combined, and
the person must be monitored very closely and adjust-
ments made in the warfarin dose if this combination
must be used. There is a decrease in the effectiveness of
hormonal contraceptives if they are taken concurrently
with these drugs; use of a barrier contraceptive should
be suggested.
Care considerations for
people receiving an antiemetic agent
Assessment: History and examination
■
■
Assess for
possible contraindications or cautions
:
history of allergy to antiemetic
to avoid potential
hypersensitivity reactions
; impaired renal or
hepatic function,
which could interfere with the
metabolism or excretion of the drug
; coma or
semiconscious state, CNS depression or CNS
injury,
which could be exacerbated by the CNS-
depressing effects of the drug
; hypotension or
hypertension,
which could be affected by the CNS
effects of the drug
; active peptic ulcer,
which could
be exacerbated by the GI effects of the drug
; and
current status of pregnancy and breastfeeding
because of the potential for adverse effects on the
fetus or breastfeeding infant.
■
■
Perform a physical examination
to establish
baseline data before beginning therapy and during
therapy to determine the effectiveness of the drug
and evaluate for the occurrence of any adverse
effects associated with drug therapy.
■
■
Assess the person’s neurological status, including
level of orientation, affect and reflexes,
to monitor
for CNS effects and to rule out underlying CNS
problems that could be a contraindication.
■
■
Assess cardiopulmonary status, including baseline
pulse and blood pressure,
to evaluate effects on the
cardiovascular system.
■
■
Inspect the skin for colour and evidence of lesion
or rash
to evaluate for photosensitivity and
adverse effects of the drug.
■
■
Examine the abdomen, including the liver, and
auscultate bowel sounds
to evaluate GI function
and motility, rule out underlying medical problems
and identify possible adverse drug effects.
■
■
Assess complaints of nausea and evaluate emesis;
note colour, amount and frequency of vomiting
episodes
to determine the need for therapy.
■
■
Monitor laboratory test results, including liver
and renal function tests,
to monitor for potential
problems with metabolism or excretion.
Implementation with rationale
■
■
Assure that route of administration is appropriate
for each person
to ensure therapeutic effects
and decrease adverse effects
: if used to prevent
motion sickness, should be given 30 minutes
before activity that involves motion; some oral
tablets can be placed in the mouth and allowed
to dissolve slowly; rectal suppositories should be
inserted high into the rectum; IV infusions should
be run slowly, monitoring the person for CNS
depression.
■
■
Assess the person carefully for any potential
drug–drug interactions if giving antiemetics in
combination with other drugs
to avert potentially
serious drug–drug interactions.
■
■
Provide comfort and safety measures, including
mouth care, ready access to bathroom facilities,
assistance with ambulation and periodic
orientation, ice chips to suck, protection from
sun exposure and remedial measures to treat
dehydration if it occurs,
to protect the person
from injury and to increase comfort.
■
■
Provide support and encouragement, as well as
other measures (quiet environment, carbonated
drinks, deep breathing),
to help the person cope
with the discomfort of nausea and vomiting and
drug effects.
■
■
Provide thorough teaching, including the drug
name and prescribed dosage; the schedule and
method for administration; the need to avoid
alcohol and other CNS depressants (if the
person is not hospitalised); signs and symptoms
of adverse effects and measures to minimise or
prevent them; the use of sunscreen and protective
clothing when outside; comfort measures to reduce
feelings of nausea, such as adequate ventilation,
deep breathing and a quiet environment; the
importance of fluid intake and signs and symptoms
of dehydration that should be reported to the
healthcare provider; safety measures, such as
assistance with ambulation and gradual position
changes; the need to notify the healthcare provider
before using any OTC medications; and the
importance of periodic monitoring and evaluation
to enhance knowledge about drug therapy and to
promote compliance.
Evaluation
■
■
Monitor the response to the drug (relief of nausea
and vomiting).
■
■
Monitor for adverse effects (dizziness, confusion,
GI alterations, cardiac arrhythmias, hypotension,
gynaecomastia, pink- to brown-tinged urine,
photosensitivity).
