What is a potential side effect of taking potassium iodide?

Taking potassium iodide can lead to throat irritation as a potential side effect. This occurs because the medication is typically administered in tablet form or as a solution, and when ingested, it can cause a temporary discomfort or irritation in the throat as it passes through. This side effect is most often mild and resolves quickly.

In contrast, the other listed options are not commonly associated with potassium iodide use. While increased anxiety, weight gain, and vision changes may arise due to a variety of health conditions or other medications, they are not recognized as direct side effects of potassium iodide. This specificity reinforces the appropriateness of throat irritation as the correct answer.