Classifications: antineoplastic; alkylating agent; Therapeutic: antineoplastic
Pregnancy Category: D
2 mg tablets; 6 mg/mL injection
Potent cytotoxic alkylating agent that may be mutagenic or carcinogenic, and cell cycle nonspecific. Reduces total granulocyte
mass but has little effect on lymphocytes and platelets except in large doses. May cause widespread epithelial cellular dysplasia
severe enough to make it difficult to interpret exfoliative cytologic examinations.
Causes cell death by acting predominantly on slowly proliferating stem cells by inducing cross linkage in DNA, thus blocking
Palliative treatment of chronic myelogenous (myeloid, granulocytic, myelocytic) leukemia for patients no longer responsive
to radiation therapy or to previously tried antineoplastics. Does not appreciably extend survival time. Stem cell transplant
Polycythemia vera, severe thrombocytosis, as adjunct in treatment of myelofibrosis, allogeneic bone transplantation in patients
with acute nonlymphocytic leukemia.
Therapy-resistant chronic lymphocytic leukemia; lymphoblastic crisis of chronic myelogenous leukemia; bone marrow depression,
immunizations (patient and household members), chickenpox (including recent exposure), herpetic infections; pregnancy (category
Men and women in childbearing years; hepatic disease; history of gout or urate renal stones; prior irradiation or chemotherapy.
Route & Dosage
|Chronic Myelogenous Leukemia
Adult: PO 48 mg/d until maximal clinical and hematologic improvement, may use 14 mg/d if remission is shorter than 3 mo
Child: PO 0.060.12 mg/kg/d or 1.84.6 mg/m2
Stem Cell Transplant Conditioning
Adult: IV (used with cyclophosphamide) 0.8mg/kg IBW or ABW (whichever is lower) q6h x 4 d
In severely obese patients, use adjusted ideal body weight = IBW + 0.25 x (actual weight IBW).
- Give at same time each day.
- Give on an empty stomach to minimize nausea and vomiting.
- Store in tightly capped, light-resistant container at 15°30° C (59°86° F), unless otherwise
PREPARE: Intermittent: Prepare a volume of NS or D5W IV solution that is 10 times the volume of busulfan needed. Using a 5 micron nylon filter
(supplied), withdraw the needed dose of busulfan. Remove needle and filter and use a new, nonfiltered needle to add busulfan
to the IV fluid. (Always add busulfan to IV fluid rather than IV fluid to busulfan.) Mix by inverting the IV bag several
ADMINISTER: Intermittent: Infuse via a central venous catheter over 2 h. Flush line before/after infusion with at least 5 mL D5W or NS.
Adverse Effects (≥1%)Hematologic:
Major toxic effects are related to bone marrow failure; agranulocytosis
, anemia. Urogenital:
Flank pain, renal
calculi, uric acid nephropathy, acute renal failure,
gynecomastia, testicular atrophy, azoospermia, impotence, sterility in males, ovarian suppression, menstrual changes, amenorrhea
(potentially irreversible), menopausal symptoms
Irreversible pulmonary fibrosis
("busulfan lung"). Skin: Alopecia
, hyperpigmentation. Other:
Endocardial fibrosis, dizziness, cholestatic jaundice
Diagnostic Test Interference
Busulfan may decrease urinary 17-OHCS excretion, and may increase blood and urine uric acid levels. Drug-induced cellular dysplasia may interfere with interpretation of cytologic studies.
InteractionsDrug: Probenecid, sulfinpyrazone
may increase uric acid
Readily from GI tract. Peak:
4 h. Duration:
4 h. Metabolism:
In liver by CYP3A4. Elimination:
1050% in urine within 48 h.
Assessment & Drug Effects
- Monitor for therapeutic effectiveness: Normal leukocyte count is usually achieved in about 2 mo.
- Monitor the following: Vital signs, weight, I&O ratio and pattern. Urge patient to increase fluid intake to 1012 (8
oz) glasses daily (if allowed) to assure adequate urinary output.
- Monitor for and report symptoms suggestive of superinfection (see Appendix F), particularly when patient develops leukopenia.
- Lab test: Baseline Hgb, Hct, WBC with differential, platelet count, liver function, kidney function, serum uric acid; repeat
at least weekly.
- Avoid invasive procedures during periods of platelet count depression.
Patient & Family Education
- Report to physician any of the following: Easy bruising or bleeding, cloudy or pink urine, dark or black stools; sore mouth
or throat, unusual fatigue, blurred vision, flank or joint pain, swelling of lower legs and feet; yellowing white of eye,
dark urine, light-colored stools, abdominal discomfort, or itching (hepatotoxicity).
- Use contraceptive measures during busulfan therapy and for at least 3 mo after drug is withdrawn.