Vincristine is included as part of a chemotherapy regimen for a patient with acute lymphoblastic leukaemia. It is essential that the medicine is administered using the correct route to prevent a potentially fatal medication error. Which is the correct route of administration?

• A. Intramuscular
• B. Subcutaneous
• C. Oral
• D. Intravenous

Answer: (D)

Vincristine must be given by the intravenous route because it is dosed and infused through the bloodstream as part of standard ALL regimens, with safeguards to prevent it from entering the spinal canal. The most dangerous error is giving it intrathecally; inadvertent intrathecal administration has caused fatal neurotoxicity, so strict protocols ensure vincristine is never injected into the intrathecal space. Other routes (intramuscular, subcutaneous, or oral) are inappropriate for achieving the correct systemic exposure and can lead to ineffective treatment or different toxicity. Therefore, the correct route is intravenous.