Introduction to Sodium Stearyl Fumarate as a pharmaceutical excipient

Sodium Stearyl Fumarate a pharmaceutical excipient

Sodium Stearyl Fumarate (SSF) is an excipient widely used in the pharmaceutical industry as a lubricant and anti-adherent in various formulations. It is a white or almost white, odorless, and tasteless powder that is soluble in water and alcohol.

• Chemical Formula: C22H39NaO4
• Chemical name: 2-Butenedioic acidiconoctadecyl ester, sodium salt
• CAS number: 4070-80-8
• EINECS number:  223-781-1

Manufacturing Process of Sodium Stearyl Fumarate

Sodium Stearyl Fumarate is derived from stearic acid and fumaric acid. The process involves the esterification of stearic acid with fumaric acid in the presence of sodium hydroxide. The reaction yields sodium stearyl fumarate along with water as a by-product. The product is then purified and dried to obtain the final powder form.

Sources

Sodium Stearyl Fumarate is a synthetic compound and is not found in nature. It is manufactured in pharmaceutical-grade under strict quality control measures to ensure its purity and compliance with regulatory requirements.

General uses of Sodium Stearyl Fumarate

SSF is primarily used as a lubricant and anti-adherent in various dosage forms, including tablets, capsules, and granules. It improves the flowability and compressibility of powders, reduces tablet sticking to punches, and enhances the disintegration and dissolution properties of tablets. Additionally, it is also used as a coating agent in tablet formulations to improve the appearance and taste of tablets.

Specific Uses per Dosage Form

Tablets

Sodium Stearyl Fumarate is commonly used in tablet formulations as a lubricant and anti-adherent to improve powder flowability, reduce tablet sticking, and enhance the dissolution properties of the tablet. The normal quantity of Sodium Stearyl Fumarate used in tablets is between 0.5% to 5% w/w of the total tablet weight. However, the quantity may vary depending on the specific formulation requirements. SSF can be used in wet and dry granulation as well as in direct compression and continuous manufacturing processes.

Coated Tablets

In coated tablet formulations, Sodium Stearyl Fumarate is used as a coating agent to improve the appearance, taste, and stability of the tablet. The normal quantity of Sodium Stearyl Fumarate used in coated tablets is between 0.5% to 5% w/w of the total tablet weight.

Capsules

In capsule formulations, Sodium Stearyl Fumarate is used as a lubricant and anti-adherent to reduce adhesion between the capsule shell and contents. The normal quantity of Sodium Stearyl Fumarate used in capsules is between 0.25% to 2.5% w/w of the total capsule weight.

Granules

Sodium Stearyl Fumarate is used as a lubricant in granule formulations to improve powder flowability. The normal quantity of Sodium Stearyl Fumarate used in granules is between 0.5% to 5% w/w of the total granule weight.

The normal quantity of Sodium Stearyl Fumarate used in pharmaceutical formulations varies based on the dosage form and specific formulation requirements. The typical quantities range from 0.25% to 5% w/w of the total weight of the dosage form. It is essential to adhere to these quantities to ensure the optimal performance of Sodium Stearyl Fumarate in the final product.

Advantates of Sodium Stearyl Fumarate vs. other Lubricants

Sodium Stearyl Fumarate offers several advantages compared to other lubricants used in the pharmaceutical industry, such as magnesium stearate, stearic acid, and talc. Here are some of the advantages:

Improved tablet dissolution

Sodium Stearyl Fumarate is more hydrophilic than magnesium stearate, which is hydrophobic. This hydrophilicity of Sodium Stearyl Fumarate improves the wettability of the tablet, leading to faster disintegration and dissolution of the tablet.

Better compatibility with active ingredients

Sodium Stearyl Fumarate has a better compatibility profile than magnesium stearate with some active ingredients that are sensitive to acidic or alkaline conditions. Sodium Stearyl Fumarate is pH-independent, making it a better choice for formulating active ingredients that require a neutral or alkaline environment. Sodium stearyl fumarate is reported to be incompatible with chlorhexidine acetate (1).

Known compatibility issue of magnesium stearate (2)

• Antiviral: Acyclovir
• Anti-inflammatory: Aspirin Ibuproxam Indomethacin Ketoprofen
• Antidiabetic: Glipizide Chlorpropamide Glimepiride Glibenclamide
• Antihypertensive: Captopril Fosinopril Moexipril Oxprenolol Quinapril
• Antibiotic: Cephalexin Erythromycin Nalidixic Acid Oxacillin Penicillin G Antimalarial: Primaquine
• Antiemetic: Promethazine
• Antiamoebic: Albendazole
• Anticancer: ß-lapachone
• Anticoagulant: Clopidogrel
• Antihistaminic: Doxylamine
• Hypnotic: Temazepam

Reduced film coating time

Sodium Stearyl Fumarate is commonly used as a coating agent for tablets. The hydrophilic nature of Sodium Stearyl Fumarate helps in the faster spreading of the coating solution, reducing the coating time.

Improved stability

Sodium Stearyl Fumarate is a more stable lubricant than magnesium stearate. Sodium Stearyl Fumarate has a lower tendency to undergo hydrolysis or oxidation, leading to improved stability of the final product.

Preferred use of Sodium Stearyl Fumerate (SSF)  over magnesium stearate (3):

In conclusion, Sodium Stearyl Fumarate is a widely used excipient in the pharmaceutical industry due to its lubricating and anti-adherent properties.

Sodium Stearyl Fumarate Excipients on pharmaexcipients.com

Product	Company
PROSOLV® EASYtab SP LM	JRS Pharma
PROSOLV® EASYtab SP	JRS Pharma
ALUBRA PG 100	IFF
LubriSANAQ®	Pharmatrans SANAQ
Lubristar	Gangwal Healthcare Private Limited
PRUV®	JRS Pharma
Advantose 100	SPI Pharma
Kollitab™ DC 87 L	BASF

 

References

• Handbook of Pharmaceutical Excipients
• Sonali S. Bharate, Sandip B. Bharate, and Amrita N. Bajaj; Interactions and incompatibilities of pharmaceutical excipients with active pharmaceutical ingredients: a comprehensive review; J. Excipients and Food Chem. 1(3) 2010; November 2010
• PRUV ® (Sodium Stearyl Fumerate) product brochure from JRS Pharma