Sodium Stearyl Fumarate

About Sodium Stearyl Fumarate

Sodium stearyl fumarate is a water-soluble lubricant used in the pharmaceutical industry for compressing tablets (\"tableting\"). Sodium stearyl fumarate is an inert, hydrophilic, tablet lubricant, useful in situations where other lubricating agents (i.e., magnesium stearate) fail to provide tablets of adequate stability, hardness, content uniformity, disintegration and dissolution rate.

Sodium stearyl fumarate is an effective tablet lubricant and reduces the friction to about the same degree as magnesium stearate. It appears slightly less effective to counteract the adhesion to the punches. It affects the disintegration time and the tablet strength in a similar way as magnesium stearate.

The particle size of sodium stearyl fumarate is of great importance for all these effects and they correlate better to the surface area of added lubricant than to the actual amount. A micronized lubricant is more efficient than a coarse fraction and it is important that the surface area is standardized to obtain reproducible effects.

Prolonged mixing with sodium stearyl fumarate appears to improve the lubricating and the antiadhesive effect with less negative effects on the disintegration than magnesium stearate. The tablet strength may be reduced by prolonged mixing. In formulations where magnesium stearate causes problems sodium stearyl fumarate may be a good alternative.