A basis particle comprises a basic or acidic basis particle coated by a water-insoluble coating film, wherein the water-insoluble coating film contains a substance that is acidic with respect to the basic basis or basic with respect to the acidic basis. According to the basis particles (i.e., a main ingredient or an active drug)of the present invention, it is possible to temporarily adjust pH occurring in the immediate proximity of the basis particles by using a coating film, elution of the basis particles is suppressed and superior elution is exhibited without dependence on bodily pH. It is also possible to mask tastes such as the bitterness of the basis and it is possible to ingest drugs without sensing any bitterness.
