A 46–year-old male, Jorawar Singh presented to the emergency with muscle weakness and cramping. He has been taking hydrochlorothiazide for recently diagnosed hypertension. Which of the following is the most likely cause of his symptoms?

A decrease in the intravascular fluid volume stimulates aldosterone secretion and leads to increased excretion of potas­sium and hydrogen ions in the urine. This results in hypokalemic metabolic alkalosis, which is a common side effect of most diuretics other than the potassium-sparing class. Hypokalemia manifests with muscle weakness and cramping.