Which of the following is a common sign of hyperkalemia?

Muscle weakness is a common sign of hyperkalemia, which is an elevated level of potassium in the blood. Hyperkalemia can affect muscle and nerve function because potassium plays a critical role in maintaining cellular electrical gradients. When potassium levels are high, it can disrupt the normal functioning of these cells, leading to a reduction in muscle strength and possibly causing muscle fatigue or weakness. This symptom can be particularly concerning, as it may progress to paralysis in severe cases of hyperkalemia.

While headaches, nausea, and diarrhea can be associated with various medical conditions, they are not as directly linked to hyperkalemia as muscle weakness is. This distinction helps health professionals identify hyperkalemia in patients more effectively.