»Prepare Xanthan Gum Solution of the designated percentage strength as follows (see Pharmaceutical Compounding—Nonsterile Preparations á795ñ):

Dissolve an accurately weighed quantity of Propylparaben in Purified Water with heating to about 50and stirring.Cool,and dilute quantitatively,and stepwise if necessary,with Purified Water to obtain 90mLof solution containing 20mg of Propylparaben.Heat to about 50,and add the Methylparaben,with stirring,to dissolve.Cool,stir with a blender,slowly sift the Xanthan Gum into the vortex,and continue to blend for 2minutes after the Xanthan Gum has been added.Add 10mLof Purified Water,and blend for 5minutes.Allow to stand for 1hour for excess foam to subside,and remove most of the remaining foam by passing the solution through a strainer.Add Purified Water,if necessary,to make the final volume 100mL,and stir.[NOTE—Depending on the volume needed and the equipment available,adjust the formula proportionately.]