For the subjects using non-potassium-sparing diuretics (i.e. loop-diuretic or thiazide diuretic) without "potassium-sparing diuretics" (e.g., Triamterene or Spironolactone) OR without potassium supplementation of at least KCl 20 mEq/day whose potassium level <3.5 mEq/L (<3.5 mmol/L) at Screening.