A nurse is assessing a client who has systemic lupus erythematosus and is taking hydroxychloroquine. Which of the following adverse effects should the nurse report to the provider immediately?

A. Mild itching or skin irritation can occur with hydroxychloroquine, but it is generally not an indication for urgent intervention. These symptoms are typically minor and can be managed symptomatically unless they worsen or are accompanied by signs of an allergic reaction. B. Gastrointestinal upset, including diarrhea, nausea, or abdominal discomfort, is a common and usually mild side effect of hydroxychloroquine. While it should be monitored, it does not require immediate reporting unless severe, persistent, or causing dehydration. C. Hydroxychloroquine can cause retinal toxicity, which may present as blurred vision, difficulty reading, or visual field defects. Retinal damage can be irreversible if not detected early. Therefore, blurred vision should be reported to the healthcare provider immediately for prompt ophthalmologic evaluation. Clients taking hydroxychloroquine typically undergo baseline and periodic eye exams to monitor for retinal changes. D. Fatigue is a common symptom of SLE itself and can also occur as a mild side effect of medications, including hydroxychloroquine. While it should be monitored, it is not a sign of a serious adverse effect that requires urgent reporting.