Not Medical Advice: It depends on the kind, what it is being used for, its strength size and how it is made.
Two types of suppositories are available in the market, glycerine suppository for easing out constipation problems and the second one is paracetamol suppository which is vital to bring down high fever too.
Acetaminophen suppositories melt at body temperature. Acetaminophen enters the bloodstream and reaches maximum concentrations after an hour of administration.
Glycerin suppositories produce a bowel movement within 15 to 60 minutes after using. For best results, stay lying down for a few minutes. The suppository will melt quickly and you should feel little or no discomfort while holding it in.
Suppository bases may be conveniently classified as according to their composition and physical properties: Oleaginous (fatty) bases and water soluble or miscible bases.
Oleaginous bases include theobroma oil and synthetic triglyceride mixtures.
At ordinary room temperatures of 15° to 25°C (59° to 77°F), theobroma oil or cocoa butter, is a hard, amorphous solid, but at 30° to 35°C (86° to 95°F), i.e., at body temperature, it melts to a bland, nonirritating oil. Thus in warm climates, theobroma oil suppositories should be refrigerated.
Water soluble/water miscible bases are those containing glycerinated gelatin or the polyethylene glycol (PEG) polymers.
Glycerinated gelatin suppositories are translucent, resilient, gelatinous solids that tend to dissolve or disperse slowly in mucous secretions to provide prolonged release of active ingredients.
Polyethylene glycol polymers have received much attention as suppository bases in recent years because they possess many desirable properties. They are chemically stable, nonirritating, miscible with water and mucous secretions, and can be formulated, either by molding or compression, in a wide range of hardness and melting point.
Like glycerinated gelatin, they do not melt at body temperature, but dissolve to provide a more prolonged release than theobroma oil.
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