Potassium is needed to maintain good health. When potassium level falls below 3.5 mmol/L, Hypokalemia is diagnosed. In case of extremely low level of potassium (lower than 2.5 mmol/L) the following symptoms are appeared: malaise and fatigue. This low level of potassium can lead to severe muscle weakness and paralysis; respiratory failure; intermittent muscle spasms. It is known, foods that are good sources of potassium and low in sodium may reduce the risk of high blood pressure and stroke. Potassium supplementation is also recommended as an adjuvant antihypertensive agent for patients with essential hypertension.

Hydroflumethiazide is a thiazide diuretic that inhibits water reabsorption in the nephron by inhibiting the sodium-chloride symporter (SLC12A3) in the distal convoluted tubule, which is responsible for 5% of total sodium reabsorption. Normally, the sodium-chloride symporter transports sodium and chloride from the lumen into the epithelial cell lining the distal convoluted tubule. The energy for this is provided by a sodium gradient established by sodium-potassium ATPases on the basolateral membrane. Once sodium has entered the cell, it is transported out into the basolateral interstitium via the sodium-potassium ATPase, causing an increase in the osmolarity of the interstitium, thereby establishing an osmotic gradient for water reabsorption. By blocking the sodium-chloride symporter, Hydroflumethiazide effectively reduces the osmotic gradient and water reabsorption throughout the nephron. Hydroflumethiazide is used as adjunctive therapy in edema associated with congestive heart failure, hepatic cirrhosis, and corticosteroid and estrogen therapy. Also used in the management of hypertension either as the sole therapeutic agent or to enhance the effect of other antihypertensive drugs in the more severe forms of hypertension.