Ranitidine bismuth citrate intra-gastric floating sustained-release tablet and preparation method thereof

The invention relates to a ranitidine bismuth citrate intra-gastric floating sustained-release tablet which is composed of a tablet core containing ranitidine bismuth citrate and a coating film wrapped over the tablet core. The tablet core is prepared from raw materials at least containing, by weight, 110 to 120 parts of ranitidine bismuth citrate, 30 to 60 parts of a skeletal material, 5 to 20 parts of a foaming agent and 45 to 130 parts of a bleaching assistant. The coating film accounts for 1 to 5% of the weight of the tablet. The tablet provided by the invention can effectively adjust the rate of constant speed release of the drug ranitidine bismuth citrate and enables a steady and lasting effective plasma concentration to be obtained, so side effects of the drug, frequency of administration and influence of the drug on an in-vivo environment are reduced, and compliance of a patient is improved.