Which of the following is a common disintegrant in tablet formulations?

Sodium Starch Glycolate is widely recognized as a common disintegrant used in tablet formulations. Its primary function is to facilitate the breakdown of the tablet into smaller fragments upon contact with liquid, ensuring that the active pharmaceutical ingredients are released effectively for absorption in the gastrointestinal tract.

This disintegrant achieves its effect through a process of swelling when hydrated, which helps to rupture the tablet matrix. This property is essential for enhancing the bioavailability of the drug, particularly for formulations intended for rapid release.

In comparison, while Microcrystalline cellulose and Starch can also play roles in tablet formulations, they are not primarily classified as disintegrants. Microcrystalline cellulose is mainly utilized as a binder and filler, contributing to the mechanical integrity of the tablet, whereas Starch may serve multiple purposes such as acting as a diluent or binder alongside its disintegrant properties. Calcium carbonate, on the other hand, is primarily used as an antacid or a source of calcium in dietary supplements rather than as a disintegrant in tablet formulations.

Thus, Sodium Starch Glycolate stands out as the main disintegrant among the choices, specifically designed to achieve rapid disintegration in tablet dosage forms.