Drug Guide

Generic Name

Dexrazoxane Hydrochloride

Brand Names Zinecard, Totect

Classification

Therapeutic: Cardioprotectant, Antineoplastic agent adjunct

Pharmacological: Iron chelator, Topoisomerase II inhibitor

FDA Approved Indications

Mechanism of Action

Dexrazoxane acts as an iron chelator, reducing free radical formation that can cause tissue damage, and inhibits topoisomerase II, which is involved in DNA replication. This dual action helps protect cardiac tissue from anthracycline-induced damage and mitigates tissue injury from extravasation.

Dosage and Administration

Adult: For cardioprotection, typically 10:1 ratio of dexrazoxane to doxorubicin dose, administered IV 30 minutes prior to doxorubicin infusion.

Pediatric: Dosing based on body surface area, generally 10 times the amount of doxorubicin (e.g., for a dose of doxorubicin, dexrazoxane 10 times that amount, administered IV 30 minutes before doxorubicin).

Geriatric: Adjust as needed based on renal function, with careful monitoring.

Renal Impairment: Use with caution; doses may need adjustment based on renal function.

Hepatic Impairment: No specific adjustments well established; monitor hepatic function.

Pharmacokinetics

Absorption: Administered IV, so absorption phase is bypassed.

Distribution: Widely distributed; crosses the blood-brain barrier.

Metabolism: Metabolized in the liver through hydrolysis and conjugation.

Excretion: Excreted mainly via urine.

Half Life: Approximately 2-3 hours.

Contraindications

Precautions

Adverse Reactions - Common

Adverse Reactions - Serious

Drug-Drug Interactions

Drug-Food Interactions

N/A

Drug-Herb Interactions

N/A

Nursing Implications

Assessment: Monitor patient’s blood counts, cardiac function, and for signs of extravasation.

Diagnoses:

  • Risk for infection due to myelosuppression.
  • Risk for tissue injury due to extravasation.

Implementation: Administer IV as prescribed; premedicate as needed for nausea. Monitor infusion site closely during extravasation treatment.

Evaluation: Assess for reduction in cardiotoxicity, monitor for adverse reactions, effective prevention or treatment of extravasation.

Patient/Family Teaching

Special Considerations

Black Box Warnings:

Genetic Factors: None established.

Lab Test Interference: May affect blood counts.

Overdose Management

Signs/Symptoms: Severe myelosuppression, allergic reactions, tissue necrosis.

Treatment: Supportive care, monitor blood counts, manage symptoms, no specific antidote.

Storage and Handling

Storage: Store at controlled room temperature (20°C to 25°C).

Stability: Stable for the duration of the shelf life when stored properly.

This guide is for educational purposes only and is not intended for clinical use.