Vincristine

Vincristine In Dogs & Cats: Uses, Dosage and Side Effects

Overview

• Interferes with microtubule assembly, causing metaphase arrest and ultimately resulting in cell death.

Uses of Vincristine

• With other neoplastic agents in the treatment of canine and feline neoplastic diseases, particularly lymphoproliferative disorders.
• Management of immune-mediated thrombocytopenia to stimulate the release of platelets.
• Treatment of transmissible venereal tumour.

Dose of Vincristine in Dogs and Cats

Dogs, Cats:

• Transmissible venereal tumours: 0.5 mg/m2 (up to a maximum dose of 1 mg) i.v. q7d for 4–6 weeks.
• Other neoplastic diseases: usual doses are 0.5–0.75 mg/m2 i.v. every 1–3 weeks. (Dependent upon protocol used.)
• To increase circulating platelet numbers: 0.02 mg/kg i.v. once (limited reports of the use of vincristine to raise circulating platelet numbers in cats, in three reported cases it had minimal or no improvement to their platelet count).

Side Effects of Vincristine in Dogs and Cats

• Include peripheral neuropathy, ileus, GI tract toxicity/constipation and severe local irritation if administered perivascularly.
• Potentially myelosuppressive.

Contraindications of Vincristine in Dogs and Cats

• No information is available.

Some Notes:

• Exercise caution when using this medication in patients with hepatic disease, leucopenia, infection, or pre-existing neuromuscular conditions.
• It may be a neurotoxic substrate of P-glycoprotein, so use with care in herding breeds like collies, which may carry the ABCB1 (MDR1) gene mutation, resulting in a non-functional glycoprotein.
• The solution is locally irritating and should be administered intravenously through a carefully pre-placed catheter.