Patent ID: 7521067

Claim:
A method of making a three-layer capsule-shaped tablet comprising: formulating a first layer containing a drug ingredient and a second layer containing a drug ingredient, wherein one of the layers comprises a first colorant; formulating a non-drug ingredient containing third layer comprising a second colorant that is distinguishable from the first colorant or from no color and not containing any drug ingredient; compressing the first, second and third layers into a capsule-shaped osmotic tablet wherein the first layer is located at one end of the capsule-shaped osmotic tablet and the third layer is located at the other end of the capsule-shaped osmotic tablet and the second layer is located between the first layer and the third layer such that the formulation orientation of the tablet can be determined by detecting the color at a spot location on a side of the tablet corresponding to one or another differently-colored layer depending on the formulation orientation of the tablet; and detecting the formulation orientation of the tablet with a color detector directed at a spot location on the side of the tablet.