Studies On The Process Of Para Amino Salicylate Sodium (PAS-Na) Enteric-coated Tablets

Para amino salicylate sodium (PAS-Na) easily converted into p-amino salicylic acid in the stomach and causing gastric adverse reactions. To conquering this issue, currently on the market for p-amino salicylic acid tablets are enteric-coated tablets. PAS-Na sugar coated tablets, produced by Shanghai Sine Pharmaceutical Laboratories Co., Ltd, are also the enteric-coated tablets. Through enteric coating, the gastric adverse reaction of the p-amino salicylic acid to the stomach could be reduced, but the process of the enteric-coated tablets is much more complex. From granulating, tableting, packaging isolation layer, packaging sugar coating layer, each step plays a key role in the quality-control of the products.This study mainly focused on optimizing the preparation process of the PAS-Na enteric-coated tablets, trying to solve the unqualified problems of the product’s collapse in stomach and improve the stability of product. Through screening the prior researches of the PAS-Na enteric-coated tablets’ stomach collapse, the main impacts are dynamiting of the enteric coating layer, the sharp and the hardness of tablet core. Through the trials of different weight ratio, we acquire the best weight ratio to ensure the tablet core can be fully packaged by enteric coating layer. After adjusting the sugar coating punch, changing the shape of the tablet core, to ensure that in no broken phenomenon could be noticed in the process of rolling in the coating machine. Through researches of ratio of granulating serous and accessories adding, it showed increase in the hardness of the tablet cores, declining of friability of the tablet cores, reducing the broken phenomenon in the process of coating. Through the above process we researched, the best production process of PAS-Na enteric-coated tablets can be determined. According to the results of stability tests, the stomach collapse is qualified and the product stability is good.On the basis of previous studying and technology of the PAS-Na enteric-coated tablets, we further research on the process of the PAS-Na film coating tablets instead enteric-coated tablets. By studying the weight ratio of the buttering and enteric garment, the process of film coating can be determined. Through the stability test, the prescription is feasible.