Lecture 40: Compounding Suppositories: Calculations & Preparations

What is hand rolling?

• A plastic-like mass is prepared by triturating grated cocoa butter & active ingredients in a mortar

• Cylinder is then cute into the appropriate number of pieces which are rolled on 1 end to produce a conical shape

What is compression molding?

Necessary to omit a portion of the suppository base, based on density factors of the active ingredients

What is fusion molding?

Dispersing or dissolving the drug in the melted base

What are some rules to pouring & opening suppository molds?

• A cold or frozen mold should never be used

• To prevent layering in the suppositories, the pouring process should not be stopped until all cavities have been filled

• Aluminum molds usually required lubrication before use

• When suppository mixtures & bases cool, they contacts. Some mixtures & bases have very pronounced contractions (PEG, cocoa butter) while others have smaller ones (glycerinated gelatin, MBK)

• Contraction minimized if mixture poured just before congealing temperature

How to calibrate suppository mold?

• Each mold is capable of holding specific volume of material in each opening

• Pharmacist should calibrate each mold for usual base to have proper quantity

• First should prepare molded suppositories from base alone

• Then suppositories are weighted & average weight recorded

• Suppositories then melted & average of one suppository volume reported

What does A, B, & C represent in density factor equation?

A- average weight of blank

B- weight of medication per suppository

C- average weight of medicated suppository