Suppositories
Introduction
Suppositories are solid pharmaceutical dosage forms designed to be 
inserted into body orifices where they soften, melt, dissolve, or disperse to 
liberate the incorporated drug(s) that exert local or systemic effect.Such bases are divided into 2 major categories:
- Fatty bases; which are divided into natural fatty bases like theobroma 
oil (cocoa-butter) and synthetic fats (prepared from vegetable oils).Preparation of suppositories 
Displacement value and calculations
Because the density of each medicament varies from that of the base, 
the weight of the base required to make a suppository will vary depending 
on the drug used.For example, bismuth subgallate suppositories are used 
as astringent in treating hemorrhoids
- Suppositories for systemic effect: Drugs are sufficiently absorbed to 
exert systemic effect.Active and inactive ingredients are dispersed in an inert matrix composed of 
solid bases.- Water-soluble and water miscible bases: For example, glycerol-gelatin 
suppositories which are a mixture of glycerol and water stiffened with 
gelatin.Theobroma oil has a major drawback of undergoing polymorphism 
when overheated, and should be stored at a cool place preferred at 4 ?C.A major disadvantage of glycerol-gelatin suppositories is 
osmosis which produces a laxative effect.Theobroma oil is obtained from the roasted seeds of theobroma cocoa.Gelatin is 
a natural protein obtained from collagenous tissue, such as skin and 
bones of animals.They can 
be classified according to the site of action into 2 major types:
- Suppositories for local effects: laxative and anti-hemorrhoidal 
suppositories.For example, Anti-asthmatics, anti-rheumatics 
and analgesics suppositories.