Potassium Phosphate, Monobasic and Sodium Phosphate, Monobasic, Anhydrous

Drug Interactions The use of antacids containing magnesium, aluminum, or calcium in conjunction with phosphate preparations may bind the phosphate and prevent its absorption. Concurrent use of antihypertensives, especially diazoxide, guanethidine, hydralazine, methyldopa, or rauwolfia alkaloid; or corticosteroids, especially mineralocorticoids or corticotropin, with sodium phosphate may result in hypernatremia. Potassium-containing medications or potassium-sparing diuretics may cause hyperkalemia when used wi t h potassium phosphate. Patients should have serum potassium level determinations at periodic intervals. Plasma levels of salicylates may be increased since salicylate excretion is decreased in acidified urine. Administration of monobasic phosphates to patients stabilized on salicylates may lead to toxic salicylate levels.

INDICATONS AND USAGE K-PHOS® No. 2 is a highly effective urinary acidifier for use in patients with elevated urinary pH. This product helps keep calcium soluble and reduces odor and rash caused by ammoniacal urine. Also, by acidifying the urine, it increases the antibacterial activity of methenamine mandelate and methenamine hippurate.

DOSAGE AND ADMINISTRATION One tablet four times daily with a full glass of water. When the urine is difficult to acidify, administer one tablet every two hours not to exceed 8 tablets in a 24-hour period.

ADVERSE REACTIONS Gastrointestinal upset (diarrhea, nausea, stomach pain and vomiting) may occur with phosphate therapy. Also, bone and joint pain (possible phosphate-induced osteomalacia) could occur. The following adverse effects may be observed (primarily from sodium or potassium): headaches; dizziness; mental confusion; seizures; weakness or heaviness of legs; unusual tiredness or weakness; muscle cramps; numbness, tingling, pain, or weakness of hands or feet; numbness or tingling around lips; fast or irregular heartbeat; shortness of breath or troubled breathing; swelling of feet or lower legs; unusual weight gain; low urine output; unusual thirst.