Which chemotherapy agent is associated with mucositis as a potential reaction?

• A. Cytarabine
• B. Vincristine
• C. Rituximab
• D. Bleomycin

Answer: (A)

Mucositis occurs when chemotherapy damages rapidly dividing cells of the mucosal lining, leading to painful ulcers and inflammation. Cytarabine is an antimetabolite that disrupts DNA synthesis in these fast-turnover cells, so the oral and gastrointestinal mucosa are especially vulnerable. This makes mucositis a well-known and common toxicity with cytarabine, especially at higher doses used in leukemia regimens.

Vincristine mainly causes neurotoxicity and neuropathies, not mucosal injury as a primary effect. Rituximab, a monoclonal antibody, often has infusion-related reactions and immunosuppression rather than mucositis as a defining toxicity. Bleomycin is more notorious for pulmonary toxicity and skin reactions, with mucositis being less characteristic.

So, cytarabine is the best answer because its action directly targets rapidly renewing mucosal cells, producing mucositis as a frequent and expected side effect.