A solution that is stable at 5° C. to 30° C. for at least 24 hours, comprising: (a) water, (b) montelukast sodium； (c) a carrier material for a fast disintegrating dosage form； and (d) a component selected from a strong base, a bicarbonate salt and mixtures thereof. The solution comprising montelukast sodium is stable under conditions that are typically encountered during certain phases of the manufacturing process of fast disintegrating dosage form that contain the montelukast sodium. The solution can be used to form fast disintegrating dosage form tablets. A method of preparing a fast disintegrating dosage form tablet including preparing such solution, and forming a tablet, and a fast disintegrating dosage form that is prepared from the montelukast sodium solution are also described.
