Abstract

HIDDEN HARMS OF A CHEMOTHERAPEUTIC ALLY: A CASE SERIES ON VINCRISTINE-INDUCED MULTISYSTEM ADVERSE EFFECTS

Hana Leela John*, Manish Mohan M., Harikrishnan S.

ABSTRACT

Background: Vincristine is a vinca alkaloid extensively used in the treatment of hematological and solid malignancies. Despite its therapeutic efficacy, its clinical use is often limited by dose-dependent neurotoxicity affecting the peripheral, autonomic, and cranial nervous systems. The diverse clinical manifestations and variable onset of vincristine-induced adverse drug reactions (ADRs) necessitate early recognition and prompt intervention to prevent irreversible complications. Case Series Description: Seven patients aged 6–78 years receiving vincristine-based chemotherapy at a tertiary care hospital developed clinically significant ADRs during the course of treatment. The reported manifestations included peripheral neuropathy, paralytic ileus, gastrointestinal dysmotility, ptosis, and the rare presentation of first bite syndrome. Most reactions developed progressively withcontinued therapy. Following identification of the ADRs, vincristine was discontinued or substituted with vinblastine, resulting in clinical improvement in the majority of patients, although recovery varied according to the severity of neurotoxicity. ADR Assessment: Causality was assessed using the World Health Organization Uppsala Monitoring Centre (WHO-UMC) criteria, with most reactions classified as Probable. Based on pharmacological classification, the ADRs were categorized as Type A (Augmented) reactions. Conclusion: This case series demonstrates that vincristine-induced neurotoxicity can occur across a wide age range and involve multiple neurological and autonomic systems, including rare presentations. Early detection, vigilant monitoring throughout chemotherapy, and timely therapeutic modification are essential to minimize toxicity, prevent long-term complications, and improve patient outcomes.

Keywords: Vincristine; Neurotoxicity; Peripheral neuropathy; Paralytic ileus; Pharmacovigilance; Case series.