Pharmacologic Profile

General Use

Used in the treatment of various solid tumors, lymphomas, and leukemias. Also used in some autoimmune disorders such as rheumatoid arthritis (methotrexate). Often used in combinations to minimize individual toxicities and ↑ response. Chemotherapy may be combined with other treatment modalities such as surgery and radiation therapy. Dosages vary greatly, depending on extent of disease, other agents used, and patient's condition.

General Action and Information

Contraindications

Previous bone marrow depression or hypersensitivity. Contraindicated in pregnancy and lactation.

Precautions

Use cautiously in patients with active infections, ↓ bone marrow reserve, radiation therapy, or other debilitating illnesses. Use cautiously in women of reproductive potential.

Interactions

Allopurinol ↓ metabolism of mercaptopurine. Toxicity from methotrexate may be ↑ by other nephrotoxic drugs or larger doses of aspirin or NSAIDs. Bone marrow depression is additive. See individual drugs.

Nursing Implications

Assessment

• Monitor for bone marrow depression. Assess for bleeding (bleeding gums; bruising; petechiae; guaiac stools, urine, and emesis) and avoid IM injections and rectal temperatures if platelet count is low. Apply pressure to venipuncture sites for 10 min. Assess for signs of infection during neutropenia. Anemia may occur. Monitor for ↑ fatigue, dyspnea, and orthostatic hypotension.
• Monitor intake and output ratios, appetite, and nutritional intake. Prophylactic antiemetics may be used. Adjusting diet as tolerated may help maintain fluid and electrolyte balance and nutritional status.
• Monitor IV site carefully and ensure patency. Discontinue infusion immediately if discomfort, erythema along vein, or infiltration occurs. Tissue ulceration and necrosis may result from infiltration.
• Monitor for symptoms of gout (↑ uric acid, joint pain, edema). Encourage patient to drink ≥2 L of fluid each day. Allopurinol may be given to ↓ uric acid levels. Alkalinization of urine may be ordered to ↑ excretion of uric acid.

Implementation

• Solutions for injection should be prepared in a biologic cabinet. Wear gloves, gown, and mask while handling medication. Discard equipment in designated containers.
• Check dose carefully. Fatalities have resulted from dosing errors.

Patient/Family Teaching

• Caution patient to avoid crowds and persons with known infections. Health care provider should be informed immediately if symptoms of infection occur.
• Instruct patient to report unusual bleeding. Advise patient of thrombocytopenia precautions.
• These drugs may cause gonadal suppression; however, patient should still use birth control, as most antineoplastics are teratogenic. Advise patient to inform health care provider immediately if pregnancy is suspected.
• Discuss with patient the possibility of hair loss. Explore methods of coping.
• Instruct patient to inspect oral mucosa for erythema and ulceration. If ulceration occurs, advise patient to use sponge brush and to rinse mouth with water after eating and drinking. Topical agents may be used if mouth pain interferes with eating. Stomatitis pain may require treatment with opioid analgesics.
• Instruct patient not to receive any vaccinations without advice of health care provider. Antineoplastics may ↓ antibody response and ↑ risk of adverse reactions.
• Advise patient of need for medical follow-up and frequent lab tests.

Evaluation/Desired Outcomes

• Decrease in size and spread of tumor.
• Improvement in hematologic status in patients with leukemia.