Compositions of different densities for fast disintegrating multi-layer tablet

Described herein is a method for forming multi-layer drug dosage forms having at least two layers. In the method, a first formulation comprising a non-gelling matrix forming agent and having a first density is dosed into a preformed mold. A second formulation comprising a non-gelling matrix former and having a second density not equal to the first density is subsequently dosed into the preformed mold. Then, the combination of the formulations dosed into the mold is freeze dried to form the multi-layer dosage form having at least two layers. The use of a density difference between the first and second formulations ensures formation of a product with two distinct layers.