BCSE Practice Exam 2025 – Complete Study Resource

Hypokalemia, which refers to low levels of potassium in the blood, can lead to various symptoms primarily due to its effects on muscle and cardiac function. The correct answer, cardiac irritability, is associated with hypokalemia because potassium is crucial for maintaining the electrical stability of cardiac myocytes. Low potassium levels can lead to disruptions in the heart's normal rhythm, resulting in increased cardiac irritability, arrhythmias, and even serious complications such as ventricular tachycardia or fibrillation.

Muscle spasms can occur, but they are more typically associated with conditions like hypocalcemia or hyperexcitability of muscle cells, rather than specifically indicating hypokalemia. Tetany, which involves sustained involuntary muscle contractions and is also more linked to low calcium, does not directly relate to potassium deficiency. Increased gastrointestinal motility is generally not associated with hypokalemia; in fact, low potassium levels usually lead to decreased motility and the risk of constipation.

Thus, cardiac irritability stands out as the primary and most directly relevant symptom of hypokalemia, emphasizing the importance of potassium in cardiac function and rhythm stability.