DepoCyte

Action

Unclear. Cytotoxic effect may stem from inhibition of DNA polymerase by drug's active metabolite.

Availability

Injection (conventional form): 20 mg Liposomal injection for intrathecal use (sustained-release): 50 mg/5-ml vial Powder for injection (conventional form): 100 mg, 500 mg, 1g, 2 g

Indications and dosages

➣ To induce remission of acute nonlymphocytic leukemia

Adults: Injection (conventional form)-100 mg/m²/day by continuous I.V. infusion on days 1 through 7, or 100 mg/m² I.V. q 12 hours on days 1 through 7, given with other antineoplastics

➣ Meningeal leukemia

Adults: Injection (conventional form)-5 to 75 mg/m²/day intrathecally for 4 days, or once q 4 days. Most common dosage is 30 mg/m² q 4 days until cerebrospinal fluid is normal.

➣ Lymphomatous meningitis

Adults: Liposomal injection-50 mg intrathecally q 14 days for two doses (at weeks 1 and 3); then q 14 days for three doses (at weeks 5, 7, and 9), with one additional dose at week 13; then q 28 days for four doses

Contraindications

• Hypersensitivity to drug

• Active meningeal infection (liposomal form)

Precautions

Use cautiously in:

• renal or hepatic disease, active infection, decreased bone marrow reserve, other chronic illnesses

• pregnant or breastfeeding patients.

Administration

• Follow facility procedures for safe handling, administration, and disposal of chemotherapeutic drugs.

• For I.V. injection, reconstitute each 100 mg with 5 ml of diluent (if necessary), and give each 100-mg dose over 1 to 3 minutes. For I.V. infusion, dilute further with 50 to 100 ml of dextrose 5% in water or normal saline solution, and infuse over 30 minutes to 24 hours (depending on dosage and concentration).

• Be aware that conventional and liposomal forms can be administered intrathecally.

☞ Don't use intrathecal route for formulations containing benzyl alcohol.

• When giving conventional form intrathecally, reconstitute with autologous spinal fluid or preservative-free normal saline solution for injection. Use immediately.

• Patients receiving intrathecal cytarabine should be treated concurrently with dexamethasone to mitigate symptoms of chemical arachnoiditis.

Adverse reactions

CNS: malaise, dizziness, headache, neuritis, neurotoxicity, chemical arachnoiditis

CV: chest pain, thrombophlebitis

EENT: conjunctivitis, visual disturbances including permanent blindness (with liposomal form)

GI: nausea, vomiting, diarrhea, abdominal pain, anal ulcers, esophagitis, esophageal ulcers, oral ulcers (in 5 to 10 days), anorexia, bowel necrosis

GU: urinary retention, renal dysfunction

Hematologic: anemia, megaloblastosis, reticulocytopenia, leukopenia, thrombocytopenia

Hepatic: hepatic dysfunction

Metabolic: hyperuricemia

Musculoskeletal: muscle ache, bone pain

Respiratory: pneumonia, shortness of breath

Skin: rash, pruritus, freckling, skin ulcers, urticaria, alopecia

Other: flulike symptoms, edema, infection, fever, cellulitis at injection site, anaphylaxis, infection (mild to fatal)

Interactions

Drug-drug. Digoxin: decreased digoxin blood level

Fluorocytosine: decreased fluorocytosine blood level

Gentamicin: decreased gentamicin effects

Drug-diagnostic tests. Hemoglobin, platelets, red blood cells, reticulocytes, white blood cells: decreased values

Megaloblasts, uric acid: increased levels

Patient monitoring

• Observe for signs and symptoms of cytarabine syndrome (malaise, fever, muscle ache, bone pain, occasional chest pain, maculopapular rash, and conjunctivitis).

☞ When giving liposomal form, assess for signs and symptoms of chemical arachnoiditis, such as neck rigidity and pain, nausea, vomiting, headache, fever, and back pain.

• Monitor liver function test results, CBC with differential, platelet count, blood urea nitrogen, and serum creatinine and uric acid levels.

☞ Observe closely for signs and symptoms of infection, which could become severe and fatal.

Patient teaching

☞ Tell patient to contact prescriber immediately if he develops signs or symptoms of infection, cytarabine syndrome (malaise, fever, muscle ache, bone pain, chest pain, rash, eye infection), or chemical arachnoiditis (neck rigidity or pain, nausea, vomiting, headache, fever, or back pain).

☞ Tell patient that drug makes him more susceptible to infection. Advise him to avoid crowds and exposure to illness.

• Advise patient to increase fluid intake, to promote uric acid excretion.

• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs and tests mentioned above.

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