Required data:
(1) average weight of blank in grams
(2) weight of medication to be added per suppository in grams
(3) average weight of a medicated suppository containing 0.1 gram medication
(4) number of suppositories to be formulated
density factor =
= (weight of medication per suppository) / ((average weight of blank) – (average weight of medicated suppository) + (weight of medication per suppository))
replacement value of the suppository base in grams =
= (weight of medication in grams) / (density factor)
amount of suppository base required per suppository in grams =
= (average weight of blank in grams) – (replacement value in grams)
To prepare N suppositories, the following ingredients will be required:
weight of medication in grams =
= N * (grams medication per suppository)
weight of base in grams =
= N * (amount of suppository base in grams)
If the average weight of a medicated suppository is not known, then it can be estimated by:
(1) Weigh sufficient suppository base to formulate 10 suppositories.
(2) Weigh 1 gram of the medication to be added, yielding 0.1 grams per suppository.
(3) Prepare the 10 medicated suppositories.
(4) Determine the average weight for the 10 medicated suppositories.
