Sodium Phosphates Oral Solution
» Sodium Phosphates Oral Solution is a solution of Dibasic Sodium Phosphate and Monobasic Sodium Phosphate, or Dibasic Sodium Phosphate and Phosphoric Acid, in Purified Water. It contains, in each 100 mL, not less than 16.2 g and not more than 19.8 g of dibasic sodium phosphate (Na2HPO4·7H2O), and not less than 43.2 g and not more than 52.8 g of monobasic sodium phosphate (NaH2PO4·H2O).
Packaging and storage— Preserve in tight containers.
Identification— It responds to the tests for Sodium 191 and for Phosphate 191.
Specific gravity 841: between 1.333 and 1.366.
pH 791: between 4.4 and 5.2.
Assay— Pipet 25.0 mL of Oral Solution into a 500-mL volumetric flask, dilute with water to volume, and mix. Transfer 25.0 mL of this stock solution to a 250-mL beaker, and add 15.0 mL of 0.5 N sodium hydroxide and 75 mL of water. Proceed as directed in the Assay under Sodium Phosphates Rectal Solution, beginning with “Titrate the excess base.”
Auxiliary Information— Please check for your question in the FAQs before contacting USP.
Topic/Question Contact Expert Committee
Monograph Elena Gonikberg, Ph.D.
Principal Scientific Liaison
(SM32010) Monographs - Small Molecules 3
USP35–NF30 Page 4669