NCLEX Review Guide: Antitumor Antibiotic Medications

Mechanism of Action

• Antitumor antibiotics are cytotoxic agents that work by intercalating between DNA base pairs, preventing DNA replication and transcription in rapidly dividing cancer cells.
• These medications are cell cycle non-specific, meaning they can kill cancer cells in any phase of the cell cycle, making them effective against various tumor types.

Doxorubicin (Adriamycin)

• Cardiotoxicity is the most serious adverse effect - monitor cumulative lifetime dose and perform baseline and periodic ECGs and echocardiograms.
• Causes characteristic red-orange discoloration of urine for 1-2 days after administration, which is normal and expected.
• Administered via central venous access only due to severe tissue necrosis if extravasation occurs.

Bleomycin (Blenoxane)

• Pulmonary fibrosis is the dose-limiting toxicity - monitor for dry cough, dyspnea, and decreased oxygen saturation.
• Unique among antitumor antibiotics because it has minimal bone marrow suppression.
• Can cause hyperpigmentation and skin changes including thickening and ulceration.

Mitomycin (Mutamycin)

• Causes severe delayed bone marrow suppression with nadir occurring 4-6 weeks after administration.
• Hemolytic uremic syndrome (HUS) is a rare but serious complication - monitor for thrombocytopenia, hemolytic anemia, and renal dysfunction.

Pre-Administration Assessment

1. Obtain baseline CBC with differential, liver function tests, and renal function tests
2. Assess cardiac function with ECG and echocardiogram (especially for doxorubicin)
3. Evaluate pulmonary function with chest X-ray and PFTs (especially for bleomycin)
4. Verify central venous access patency before vesicant administration

Administration Guidelines

• Use personal protective equipment (PPE) including double gloves, gown, and eye protection when handling cytotoxic drugs.
• Administer slowly via central line for vesicants, monitoring for signs of extravasation throughout infusion.
• Pre-medicate with antiemetics as most antitumor antibiotics cause moderate to severe nausea and vomiting.

Quick Check Questions

• □ Can you identify the dose-limiting toxicity for each major antitumor antibiotic?
• □ Do you know which antitumor antibiotic causes minimal bone marrow suppression?
• □ Can you explain why doxorubicin must be given via central line?
• □ Do you understand the timeline for mitomycin's delayed toxicity?