Excipient (pharmacologically inactive substance)

What is it?

Magnesium stearate (Mg(C18H3502)2 or octadecanoic acid) is a solid, white powder at room temperature. It is a FDA-approved inactive ingredient commonly used in the pharmaceutical industry as a lubricant and release agent in the manufacture of tablet, capsule, and powder dosage forms.

Magnesium stearate is generally recognized as safe by the FDA.^[1] Magnesium stearate exists as a salt form and is useful for it's lubricating properties for capsules and tablets in industry. It is used to help prevent pharmaceutical ingredients from adhering to industry equipment.^[2] Magnesium stearate may be derived from both plant and animal sources.