A nurse is teaching a client with rheumatoid arthritis about the use of methotrexate. Which statement by the client indicates a correct understanding of the safety precautions associated with methotrexate therapy?

Rationale: A. Methotrexate has the potential to cause serious toxicities, including bone marrow suppression, liver toxicity, and renal impairment. Because of these risks, patients require frequent monitoring of complete blood count (CBC), liver function tests (LFTs), and renal function. Initially, labs are typically checked every 4–8 weeks when starting or adjusting therapy, and periodically thereafter. Waiting an entire year to have labs drawn would be unsafe and could delay the detection of life-threatening complications. B. Methotrexate is teratogenic and can cause severe fetal abnormalities. Clients of childbearing age must use effective contraception throughout therapy. Stopping oral contraceptives would increase the risk of pregnancy, which is contraindicated while taking methotrexate. Patient education must emphasize consistent contraceptive use during treatment. C. Mouth sores, also called stomatitis or mucositis, are an early sign of methotrexate toxicity, often related to bone marrow suppression or mucosal irritation. Reporting these symptoms promptly allows the healthcare provider to adjust the dose, provide supportive care, or intervene before more serious complications occur, such as infection, severe anemia, or bleeding. This demonstrates that the client understands the importance of monitoring for early signs of adverse effects. D. Methotrexate is immunosuppressive, so live vaccines (including MMR, varicella, and some others) are contraindicated during therapy because they can cause vaccine-related infection. Patients should receive non-live vaccines as appropriate and consult their provider before vaccination.