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P A R T 2
Chemotherapeutic agents
■■
Antimetabolites inhibit DNA production by
inhibiting metabolites needed for the synthesis of
DNA in susceptible cells.
■■
Antimetabolites are S phase cell cycle–specific and
are used for some leukaemias, as well as some GI and
basal cell cancers.
■■
Bone marrow suppression, alopecia and toxic GI
effects are common adverse effects of antimetabolites.
KEY POINTS
Care considerations for
people receiving antimetabolites
Assessment: History and examination
■
■
Assess for contraindications and cautions:
history of allergy to the specific antimetabolite
to avoid hypersensitivity reactions
; bone marrow
suppression
to prevent further suppression
;
renal or hepatic dysfunction
that might interfere
with drug metabolism and excretion
; current
status related to pregnancy or breastfeeding
to prevent potentially serious effects to the fetus or
breastfeeding baby
; and a history of GI ulcerative
disease,
which could be exacerbated with the use
of these drugs
.
■
■
Perform a physical assessment
to establish baseline
data for determining the effectiveness of the
drug and the occurrence of any adverse effects
associated with drug therapy
.
■
■
Assess orientation and reflexes
to evaluate any
CNS effects
; respiratory rate and adventitious
sounds
to monitor the disease and to evaluate
for respiratory or hypersensitivity effects
; pulse,
rhythm and cardiac auscultation
to monitor for
systemic or cardiovascular effects
; and bowel
sounds and mucous membrane status
to monitor
for GI effects
.
■
■
Monitor the results of laboratory tests such as FBC
with differential to identify possible bone marrow
suppression and toxic drug effects; and renal
and liver function tests
to determine the need for
possible dose adjustment and toxic drug effects
.
Implementation with rationale
■
■
Arrange for blood tests to monitor bone marrow
function before, periodically during, and for
at least 3 weeks after therapy
to arrange to
discontinue the drug or reduce the dose as needed
.
■
■
Administer medication according to the scheduled
protocol and in combination with other drugs
as indicated
to improve the effectiveness of drug
therapy
.
■
■
Ensure the person is well hydrated
to decrease the
risk of renal toxicity
.
■
■
Provide small, frequent meals, frequent mouth care
and dietary consultation as appropriate
to maintain
nutrition when GI effects are severe
. Anticipate the
use of antiemetics as necessary. (See Box 14.5.)
■
■
Arrange for proper head covering at extremes of
temperature if alopecia occurs; a wig, scarf or hat
is important for maintaining body temperature
.
If alopecia is an anticipated effect of drug therapy,
advise the person to obtain a wig or head covering
before the condition occurs
to promote self-esteem
and a positive body image
.
■
■
Protect the individual from exposure to infections
because bone marrow suppression will limit
immune/inflammatory responses
.
■
■
Provide support and encouragement to help the
person cope with the diagnosis and the effects of
drug therapy.
■
■
Provide the following teaching:
–– Follow the appropriate dosage regimen, including
dates to return for further doses. People need
to be reminded to report all other drugs and
alternative therapies that they might be using.
Box 14.7 discusses alternative therapies often
used by cancer sufferers that could interact with
their drug regimen.
–– Maintain nutrition if GI effects are severe.
–– Cover the head at extremes of temperature if
alopecia is anticipated.
–– Plan for appropriate rest periods because fatigue
and weakness are common effects of the drugs.
–– Avoid situations that might lead to infection,
including crowded places, sick people and
working in the soil.
–– Use safety measures such as not driving or using
dangerous equipment, due to possible dizziness,
headache and drowsiness.
–– Think about consulting with a healthcare
provider, if appropriate, due to the possibility of
impaired fertility.
–– Use barrier contraceptives to reduce the risk of
pregnancy during therapy.
Evaluation
■
■
Monitor response to the drug (alleviation of cancer
being treated, palliation of signs and symptoms
of cancer, palliation of rheumatoid arthritis or
psoriasis).
■
■
Monitor for adverse effects (bone marrow
suppression, GI toxicity, neurotoxicity, alopecia,
renal or hepatic dysfunction).
■
■
Evaluate the effectiveness of the teaching plan
(person can name the drug, dosage, possible
adverse effects to watch for and specific measures
to help avoid adverse effects).
■
■
Monitor the effectiveness of comfort and safety
measures and compliance with the regimen.
