A 42-year-old woman decides to lose weight on a diet prescribed by an anorexic friend. She loses about 30 pounds in 45 days, but her serum potassium level falls to 2.1 mmol/L (normal: 3.5 to 5.0 mmol/L). Which of the following changes is most likely to occur in this young woman?

Question

Quizplus · Accepted Answer

The low serum potassium level indicates a state of hypokalemia. Hypokalemia can cause hyperpolarization of the resting membrane potential, making it more difficult for excitation and depolarization to occur. This can lead to muscle weakness, cramping, and arrhythmias. Depolarization of the resting membrane potential (A) and increased intracellular potassium concentration (C) are not typical changes seen in hypokalemia. The potassium equilibrium potential becoming less negative (D) would actually make the hyperkalemia worse, not improve it, so this is also not the correct choice.

A 42-Year-Old Woman Decides to Lose Weight on a Diet