Studies on gynecological hydrophilic lactic acid preparations. Part 8: use of chitosan as lactic acid carrier in intravaginal tablets.

Hydrophilic intravaginal tablets based on methylcellulose and containing lactic acid component with chitosan undergo swelling under standard conditions. A high flow-limit of the gel that originates from the tablets as well as its dynamic viscosity should allow for the durable dosage form in the vagina. By choosing the 1:1 ratio of lactic acid to chitosan, it is possible to obtain tablets disintegrating into a gelform at physiological pH range of 3.8-4.4. An increase in the amount of lactic acid in the complex in relation to the polymer up to 2:1 and 3:1 ratios results in gels with a lower pH. These gels possess an acid reserve that might act to neutralize the excess of alkali present in severe vaginal infections.