The problem with which the present invention is concerned is providing a novel pharmaceutical preparation, the restrictions on the administration of which to a patient are more relaxed than those of a conventional spherical carbon adsorbent, which can be simultaneously taken with other drugs and, moreover, which is reduced in dosage. The problem can be solved by a pharmaceutical preparation for oral administration comprising a porous material, wherein a means for exposing a surface of the porous material for the first time in the large intestine or a lower part of the small intestine is provided on the porous material.