It is intended to provide a process for producing unstableamorphous benzimidazole compounds having a proton pump inhibitorfunction, and stable solid preparations containing thesecompounds which are produced by blending such an amorphousbenzimidazole compound with a nontoxic base such as a basicinorganic salt, optionally forming an intermediate coating layeron the layer containing the active ingredient and optionallyfurther forming an enteric coating layer or a release-controllingcoating layer.
