Sodium stearyl fumarate is a chemical compound, sodium salt of the monooctadecyl ester of butyric acid.

It is commonly used as a lubricating agent in orally dissolving medicinal tablets. In the mold, the lubricant performs a protective action on tools acting with reduced frictional force. The lubricant acts on the kinetics of tablet disintegration, tablet friability, tablet strength, and tablet hardness. Other important functions of lubricants are:

• preventing tablets from sticking to the mold
• improving the speed of the tablet granules
• to facilitate the ejection of the tablet from the mold

It is included in a maximum percentage of 1%.

Sodium stearylfumarate also acts as an anionic surfactant (removes dirt particles).

Sodium stearyl fumarate studies

Sodium stearyl fumarate data sheet

Molecular Formula: C₂₂H₃₉NaO₄

Molecular Weight: 390.5 g/mol

CAS: 4070-80-8

UNII 7CV7WJK4UI

EC Number: 223-781-1

DSSTox Substance ID: 

MDL number  

PubChem Substance ID 

NACRES  NA.24

Synonyms: 

• Sodium octadecyl fumarate
• (E)-2-Butenedioic acid monooctadecyl ester sodium salt
•  Sodium monooctadecyl fumarate
• Sodium monooctadecyl 2-butenedioate, (E)-