Vincristine

Vinca alkaloid chemotherapy for lymphoma, IMT (stimulates megakaryocyte release), and neoplasms in dogs and cats. Vinca alkaloid antineoplastic (vincristine sulfate). Mechanism: binds tubulin → inhibits microtubule assembly → arrests mitosis at metaphase. Also stimulates platelet release from megakaryocytes via microtubule disruption → used for immune-mediated thrombocytopenia (IMT) to rapidly increase platelet count. More neurotoxic than vinblastine (peripheral neuropathy). IV only — vesicant. Key information Vinca alkaloid chemotherapeutic. CYTOTOXIC and vesicant. Handle with chemotherapy precautions. IV only — extravasation causes severe tissue necrosis. Peripheral neuropathy side effect. Refrigerate. Dispose as hazardous waste.

IV via confirmed patent catheter ONLY: administer as slow IV push or short infusion. Flush catheter with saline before and after. Wear double gloves, gown, eye protection (vesicant/cytotoxic). LABEL SYRINGE AS VESICANT. Dispose per cytotoxic protocols. NEVER administer intrathecally. Store refrigerated (2–8°C); do not freeze. If a dose is missed This medication is administered by a veterinarian or veterinary staff in a clinical setting. Missed doses are managed by your veterinary team — contact your veterinarian to reschedule.

Peripheral/autonomic neuropathy (dose-limiting): constipation, ileus, urinary retention, paresthesias. Vesicant: severe tissue necrosis with extravasation — IV only via catheter. Myelosuppression (milder than vinblastine). GI: vomiting, diarrhea. SIADH (hyponatremia). Fatal if given intrathecally.

For animals VESICANT — confirm patent IV catheter before administration; extravasation causes severe tissue necrosis. FATAL IF GIVEN INTRATHECALLY. Avoid in pregnant animals. Primarily causes peripheral and autonomic neuropathy (constipation, ileus) rather than myelosuppression. Monitor for GI motility signs. Not approved for use in food-producing animals. For people handling this medication Wear gloves when handling. CYTOTOXIC VESICANT. Wear double gloves, gown, and eye protection. Keep out of reach of children. Pregnant women and women of childbearing age should avoid contact. Teratogenic. Do not handle if pregnant or breastfeeding. FATAL if given intrathecally. If skin contact occurs, wash immediately. Severe tissue necrosis from extravasation. Dispose of waste per cytotoxic protocol.

This is a veterinary emergency. Vincristine overdose causes severe bone marrow suppression, GI toxicity, and neurotoxicity. Contact your veterinary oncologist immediately.