Edition: BP 2025 (Ph. Eur. 11.6 update)
DEFINITION
Lactic Acid Pessaries are moulded pessaries containing Lactic Acid in a suitable basis.
The pessaries comply with the requirements stated under Vaginal Preparations and with the following requirements.
Content of lactic acid, C3H6O3:
95.0 to 105.0% of the stated amount.
ASSAY
Weigh five pessaries, melt together by warming and allow to cool, stirring continuously.
Dissolve a quantity of the mass containing 1 g of Lactic Acid in 50 mL of water.
Add 50 mL of 0.5M sodium hydroxide VS, boil gently for 5 minutes, cool and titrate the excess of alkali with 0.5M hydrochloric acid VS using phenolphthalein solution R1 as indicator.
Each mL of 0.5M sodium hydroxide VS is equivalent to 45.04 mg of C3H6O3.
