Functional Category
Tablet and capsule lubricant.
Applications in Pharmaceutical Formulation
Zinc stearate is primarily used in pharmaceutical formulations as a lubricant in tablet and capsule manufacture at concentrations up to 1.5% w/w. It has also been used as a thickening and opacifying agent in cosmetic and pharmaceutical creams, and as a dusting powder.
Description
Zinc stearate occurs as a fine, white, bulky, hydrophobic powder, free from grittiness and with a faint characteristic odor.
Stability and Storage Conditions
Zinc stearate is stable and should be stored in a well-closed container in a cool, dry place.
Incompatibilities
Zinc stearate is decomposed by dilute acids. It is incompatible with strong oxidizing agents.
Safety
Zinc stearate is used in oral and topical pharmaceutical formulations, and is generally regarded as a nontoxic and nonirritant excipient. However, following inhalation, it has been associated with fatal pneumonitis, particularly in infants.(1) As a result, zinc stearate has now been removed from baby dusting powders. LD50 (rat, IP): 0.25 g/kg