Potassium phosphate is scientifically justified in the management of certain types of alkalosis, specifically hypokalemic and/or hypophosphatemic metabolic alkalosis. Metabolic alkalosis is characterized by elevated blood pH due to an excess of bicarbonate or a loss of acids (often from vomiting, diuretic use, or certain endocrine disorders). This condition frequently coexists with deficits in potassium and phosphate, as both ions are lost in urine when the body's acid-base balance is disturbed.

The administration of potassium phosphate serves a dual purpose: it corrects hypokalemia and hypophosphatemia, both common in alkalotic states, and also provides a source of acid (phosphate), which can help buffer excess base, thereby aiding in the correction of alkalosis. Clinical guidelines and pharmacology references (such as the Handbook on Injectable Drugs and Goldman-Cecil Medicine) support the use of potassium phosphate in this context, especially in hospitalized patients with simultaneous deficiencies.

Randomized controlled trials are limited, but case series and clinical experience, as well as pathophysiological rationale, provide strong support for this approach. It is not a primary therapy for alkalosis but is indicated when laboratory findings confirm low potassium and phosphate. Thus, there is scientific foundation and moderate-to-strong evidence for its use in the supportive management of alkalosis with associated electrolyte imbalances.