NCLEX Review Guide: Antineoplastic Medications

Classification and Mechanisms

• Alkylating agents (cyclophosphamide, cisplatin) work by cross-linking DNA strands, preventing cell replication during any phase of the cell cycle.
• Antimetabolites (methotrexate, 5-fluorouracil) interfere with DNA synthesis by mimicking normal metabolites required for cell division.
• Plant alkaloids (vincristine, paclitaxel) disrupt microtubule formation, preventing proper chromosome separation during mitosis.
• Antitumor antibiotics (doxorubicin, bleomycin) intercalate between DNA base pairs and generate free radicals that damage cellular components.

Hematological Toxicity

• Myelosuppression is the most common dose-limiting toxicity, with nadir (lowest counts) typically occurring 7-14 days post-treatment.
• Monitor complete blood count (CBC) with differential before each treatment cycle and implement neutropenia precautions when ANC < 1,000.
• Thrombocytopenia requires bleeding precautions when platelet count falls below 50,000, including soft toothbrush use and avoiding invasive procedures.

Gastrointestinal Toxicity

• Mucositis and stomatitis commonly occur 5-7 days after treatment, requiring frequent oral care with normal saline rinses and avoiding alcohol-based mouthwashes.
• Nausea and vomiting management includes prophylactic antiemetics (ondansetron, metoclopramide) administered 30 minutes before chemotherapy.
• Diarrhea may require fluid and electrolyte replacement, with severe cases needing antidiarrheal medications and dietary modifications.

High-Alert Medications

1. Verify patent IV access with blood return before administration
2. Administer through central line when possible for vesicant drugs
3. Monitor injection site continuously during infusion
4. Have antidote readily available (dexrazoxane for anthracyclines)
5. Stop infusion immediately if extravasation suspected

Organ-Specific Toxicities

• Cardiotoxicity from doxorubicin requires baseline ECHO or MUGA scan, with cumulative lifetime dose not exceeding 450-550 mg/m².
• Pulmonary toxicity from bleomycin manifests as pulmonary fibrosis, requiring baseline pulmonary function tests and monitoring for dyspnea.
• Nephrotoxicity from cisplatin necessitates adequate hydration (1-2L normal saline) before and after administration plus monitoring serum creatinine.
• Neurotoxicity from vincristine presents as peripheral neuropathy, requiring assessment of deep tendon reflexes and numbness/tingling.

Quick Check Questions

• □ Can you identify the four main classes of antineoplastic drugs?
• □ Do you know when hematologic nadir typically occurs?
• □ Can you list three vesicant chemotherapy drugs?
• □ Do you understand neutropenia precautions?
• □ Can you identify organ-specific toxicities for major drugs?