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P A R T 2
Chemotherapeutic agents
Clinically important drug–drug interactions
Use caution when administering imatinib with other
drugs affected by the cytochrome P450 enzyme system.
In addition, St John’s wort decreases the effectiveness
of many of these drugs and should be avoided. When
using nilotinib avoid any other drugs that are known to
prolong the QT interval.
■■
Cancer cell–specific drugs have been developed to
target processes that occur in cancer cells but not in
healthy cells. This specificity results in fewer toxic
effects than with traditional antineoplastic therapy.
■■
Protein tyrosine kinase inhibitors, epidermal
growth factor inhibitors and proteasome inhibitors
have been developed to target cancer cells
specifically.
MISCELLANEOUS ANTINEOPLASTICS
Many other agents that do not fit into one of the pre
viously discussed groups are used as antineoplastics
to cause cell death. These drugs are used for treating
a wide variety of cancers. Table 14.7 lists the unclas
sified antineoplastic drugs, their indications and any
special considerations associated with the drug. Specific
KEY POINTS
Care considerations for people receiving
cancer cell–specific agents
These are similar to care considerations for people
receiving alkylating agents.
TABLE 14.7
DRUGS IN FOCUS Miscellaneous antineoplastics
Drug name
Dosage/route
Usual indications
arsenic trioxide
(Phenasen)
Induction: 0.15 mg/kg per day IV until
remission
Consolidation: continue 3–6 weeks
after inducting for up to 25 doses
Induction and consolidation in people with
acute promyelocytic leukaemia (APL) who are
refractory to or relapsed from standard therapy
Actions:
causes damage to fusion proteins and
DNA failure, leading to cell death
Special considerations:
monitor for cardiac
toxicity; do not use during pregnancy
hydroxyurea (Hydrea)
80 mg/kg PO every third day;
20–30 mg/kg PO daily for continual
therapy
Inhibits enzymes essential for the synthesis of
DNA, causing cell death
Actions:
treatment of melanoma, ovarian cancer,
chronic myelocytic leukaemia; in combination
therapy for primary squamous cell cancers of
the head and neck; also used in the treatment of
sickle cell anaemia
Special considerations:
can cause bone marrow
depression, headache, rash, GI toxicity and
renal dysfunction; encourage person to drink
10–12 glasses of water each day while taking
this drug
irinotecan (Camptosar,
Tecan)
125 mg/m
2
IV over 90 minutes, once
a week for 4 weeks, followed by
2 weeks of rest; repeat every 6 weeks
Treatment of metastatic colon or rectal cancer
after treatment with fluorouracil (5-FU) or given
with 5-FU
Actions:
disrupts DNA strands during DNA
synthesis, causing cell death
Special considerations:
can cause severe bone
marrow depression, which regulates dose of the
drug; causes GI toxicity, dyspnoea, and alopecia
topotecan (Hycamtin)
1.5 mg/m
2
per day IV for 5 days; as part
of a 21-day course; minimum of four
courses
Treatment of people with metastatic ovarian
cancer after failure of other agents
Actions:
damages DNA strand, causing cell death
during cell division
Special considerations:
can cause severe
bone marrow depression, which regulates the
dose of the drug; total alopecia, GI toxicity and
CNS effects may also limit the use of the drug;
analgesics may be helpful
