What is a common symptom of renal failure?

Swelling of the limbs is commonly associated with renal failure due to the kidneys' impaired ability to filter and excrete excess fluids and waste products from the body. When the kidneys do not function properly, the body can retain excess fluids, leading to edema, which is the swelling observed in various parts of the body, particularly the limbs. This occurs because the kidneys play a critical role in maintaining fluid balance, and when they are not performing effectively, the result can be fluid accumulation.

In contrast, frequent headaches, changes in vision, and increased appetite are not typical primary symptoms of renal failure. Headaches can arise from various conditions and may not directly relate to kidney function. Changes in vision can be influenced by other factors such as diabetes or hypertension rather than being a direct consequence of kidney failure. Lastly, an increased appetite is generally not associated with renal failure; in fact, many individuals may experience a decrease in appetite due to the effects of toxins accumulating in the body when the kidneys are not functioning optimally.