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Magnesium Stearate

Medically reviewed by Last updated on Nov 9, 2023.

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.

List of medications using Magnesium Stearate


  1. FDA’s SCOGS database; Magnesium stearate, Report No. 60, 1979.; ID Code: 557-04-0; Accessed July 18, 2011.
  2. [2]Dave RH. Overview of pharmaceutical excipients used in tablets and capsules. Drug Topics (online). Advanstar. 10/24/2008 Accessed 08/19/2011

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.