Potassium citrate is used in the management of cystic fibrosis (CF) primarily to help correct electrolyte imbalances, particularly metabolic alkalosis and hypokalemia, which can occur in individuals with CF. Scientific evidence supports its use, though it is not a core or disease-modifying therapy for cystic fibrosis itself. In CF, patients often lose excessive amounts of electrolytes, especially potassium and chloride, through sweat. When they develop metabolic alkalosis (an elevation in blood pH due to loss of hydrogen ions or gain in bicarbonate), potassium citrate can help restore acid-base balance by providing both potassium and a base (citrate) that is metabolized to bicarbonate.

Clinical guidelines and reviews note that potassium supplementation, including potassium citrate, is indicated in CF patients who develop hypokalemia and/or metabolic alkalosis, particularly during episodes of salt depletion, vomiting, or when on diuretic therapy. While there are no large randomized controlled trials specifically of potassium citrate in CF, its use is based on well-understood pathophysiology and clinical experience, and is recommended in consensus guidelines for managing electrolyte disturbances in CF. It is not, however, used to treat the underlying disease process of cystic fibrosis or its pulmonary complications.

In summary, potassium citrate is scientifically validated as a supportive treatment for specific metabolic complications in CF, rather than as a therapy for cystic fibrosis itself.