Direct compression filler

Table 6 Comparative Properties of Some Directly Compressible Fillers ... 

There are many commercially available direct compression filler-binders. The most commonly used filler-binders include spray-dried lactose, mannitol, microcrystalline cellulose, pregelatinized starch, and dibasic calcium phosphate. Many factors affect the selection of a filler-binder for a direct compression tablet formulation. The most important requirements for a directly compressible filler-binder used in a low-dose formulation are listed below ... 

Lactose. Lactose, an animal-origin excipient, is the oldest and still one of most widely used direct compression filler-binders. Lactose is commercially available in various grades that differ in properties such as shape, particle size distribution, and flow characteristics. This permits the selection of the most suitable material for a particular application. Direct compression grades of lactose are available in three forms ... 

TABLE 7.4 Typical Physical Properties of Selected Lactose as Directly Compressible Filler-Binders... 

In addition to the hydrate form, anhydrous dibasic calcium phosphate is also a directly compressible filler-binder. This form is also nonhygroscopic and stable at room temperature. 

David ST, Augsburger LL. 1977. Plastic flow during compression of directly compressible fillers and its effect on tablet strength. J. Pharm. Sci. 66(2) 155-159. 

Coprocessed tablet excipient composed of chitin and silicon dioxide [52] Chitin is a water-insoluble hydrophilic polymer that can absorb water and function as a disintegrant. Due to the unacceptable flow and compression properties of chitin, coprecipitation with silicon dioxide was used to provide a new excipient with excellent flow, compaction and disintegration properties when compared to the individual components or commercially available direct compression fillers and disintegrants. The optimal composition of the coprocessed excipient contains a silicon concentration of about 50% (w/w). 

Tablets manufactured with DuraSolv technology contain a non-directly compressible filler and a lubricant. They may or may not contain effervescence, and the drug need not be taste masked. DuraSolv tablets are compressed at higher hardness compared to OraSolv that allows for packaging in bottles or push through blisters.

Mitrevej, A. Sinchaipanid, N. Faroongsarng, D. Spray-dried rice starch comparative evaluation of direct compression fillers. Drug Dev. Ind. Pharm. 1996, 22 (7), 587-594. 

Hammouda Y, Eshra AG, El-Banna HM. The use of sodium chloride as a directly compressible filler. Part III Drug-to-filler ratio. Pharm Ind 1978 40(9) 987-992. 

Armstrong (1998) described the following requirements for direct compression fillers ... 

Jivraj et al. (2000) have classified the direct compression fillers in terms of their disintegration and flow properties (Table 11.12). 

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