Hard fat suppository base containing polysorbate additive to improve dispersion of hydrophilic APIs in aqueous solutions or hydroalcoholic extracts.

Names & synonyms


Hard fat

EP Name

Hard fat with additive



Preferred Substance Name (FDA)
Handbook of Pharmaceutical Excipients

Suppository bases, hard fat

Chemical description

Consists of mono-, di- and triglyceride esters of fatty acids (C10 to C18), the triester fraction being predominant and containing  polysorbate 65

Key characteristics

Product form


Melting range (°C)

35 - 39

Hydroxyl value (mg KOH/g)

15 - 25

suppocire bs2x thermorheogram

Main functionnalities

Facilitates dispersion of hydrophilic APIs. Prevents the exudation of APIs.

Main formulation technologies

Suppository molding.

Associated content

Hard fats for suppositories

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  • Formulation technologies

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