Calcium Phosphate, Tribasic

Synonyms:  Calcium orthophosphate; E341(iii); hydroxylapatite; phosphoric acid calcium salt (2 : 3); precipitated calcium phosphate; tertiary calcium phosphate; Tri-Cafos; tricalcii phosphas; tricalcium diorthophosphate; tricalcium orthophosphate; tricalcium phosphate; TRI-CAL WG; TRI-TAB.

Description:  The PhEur 6.4 states that tribasic calcium phosphate consists of a mixture of calcium phosphates. It contains not less than 35.0% and not more than the equivalent of 40.0% of calcium Tribasic calcium phosphate is a white, odorless and tasteless powder

Chemical Name: Calcium hydroxide phosphate 

Tricalcium orthophosphate

Tablet and capsule diluent

• Tribasic calcium phosphate is widely used as a capsule diluent and tablet filler/binder in either direct-compression or wet-granulation processes.

• The primary bonding mechanism in compaction is plastic deformation. As with dibasic calcium phosphate, a lubricant and a disintegrant should usually be incorporated in capsule or tablet C Calcium Phosphate, Tribasic 99 formulations that include tribasic calcium phosphate.

• In some cases tribasic calcium phosphate has been used as a disintegrant.

• It is most widely used in vitamin and mineral preparations as a filler and as a binder.

• It is a source of both calcium and phosphorus, the two main osteogenic minerals for bone health.

• The bioavailability of the calcium is well known to be improved by the presence of cholecalciferol.

• Recent research reports that combinations of tribasic calcium phosphate and vitamin D3 are a cost-effective advance in bone fracture prevention

• In food applications, tribasic calcium phosphate powder is widely used as an anticaking agent. 

All calcium salts are incompatible with tetracycline antibiotics. Tribasic calcium phosphate is incompatible with tocopheryl acetate (but not tocopheryl succinate). Tribasic calcium phosphate may form sparingly soluble phosphates with hormones.

Tribasic calcium phosphate is widely used in oral pharmaceutical formulations and food products, and is generally regarded as nontoxic and nonirritant at the levels employed as a pharmaceutical excipient. Ingestion or inhalation of excessive quantities may result in the deposition of tribasic calcium phosphate crystals in tissues. These crystals may lead to inflammation and cause tissue lesions in the areas of deposition. Oral ingestion of very large quantities of tribasic calcium phosphate may cause abdominal discomfort such as nausea and vomiting.

Observe normal precautions appropriate to the circumstances and quantity of material handled. Eye protection and gloves are recommended. Handle in a well-ventilated environment since dust inhalation may be an irritant. For processes generating large amounts of dust, the use of a respirator is recommended.

Calcium phosphate, dibasic anhydrous; calcium phosphate, dibasic dihydrate.