Hard fat suppository base optimized for the formulation of analgesics and antipyretics. Confers high mechanical resistance and yields harder suppository units.

Names & synonyms


Hard fat

EP Name

Hard fat



Preferred Substance Name (FDA)

Fat, hard

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

Key characteristics

Product form


Melting range (°C)

33 - 35

Hydroxyl value (mg KOH/g)

20 - 30

Main functionnalities

Base recrystallizes rapidly and produces harder suppository units with high mechanical resistance

Main formulation technologies

Suppository molding

Associated content

Hard fats for suppositories

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Alternative dosage forms for rectal and vaginal drug delivery

  • Formulation technologies

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