A nurse is teaching a client who has rheumatoid arthritis about taking methotrexate. Which of the following information should the nurse include?

Choice A rationale Methotrexate, a disease-modifying antirheumatic drug (DMARD), can cause significant gastrointestinal and hematological toxicity. Taking it concurrently with a nonsteroidal anti-inflammatory drug (NSAID), such as ibuprofen, may increase the risk of severe NSAID side effects like gastrointestinal bleeding or nephrotoxicity due to drug interactions, and is often avoided or used with caution. Choice B rationale Methotrexate is primarily eliminated by the kidneys, and a significant adverse effect is nephrotoxicity and crystal formation in the renal tubules, particularly at higher doses. Drinking 2 to 3 liters of water per day ensures adequate hydration and promotes diuresis, which helps to flush the drug and its metabolites from the body, thereby reducing the risk of renal damage. Choice C rationale Methotrexate is known to cause nausea and vomiting, which is typically managed with antiemetics like ondansetron. However, the antiemetic should be taken before or concurrently with the methotrexate to be most effective in preventing the onset of nausea, not an hour following administration when the symptoms may have already started. Choice D rationale Methotrexate can cause oral mucositis or stomatitis (inflammation of the mucous membranes of the mouth). Rinsing the mouth regularly can help with hygiene, but an alcohol-based mouthwash is irritating and should be avoided as it can worsen the existing mucosal damage and increase pain, further contributing to discomfort.