Suppositories, ingredients cocoa butter

The calculations involved here include determination of the amount of cocoa butter needed by using the displacement values as well as the amount of other ingredients. The calculations are shown in Examples 1-3. In this section, a brief overview is provided for the method of suppository preparation with cocoa butter. The first step is to decide whether cocoa butter is appropriate for the suppositories that are required to be prepared. If the use of cocoa butter is justified, the second step is to determine the weight of the suppository. Usually the adult rectal suppository with cocoa butter is 2 g, the children s suppository is 1 g, and the glycero-gelatin suppository for vagina is 5 g. The final step involves calculation of the amounts of all ingredients needed. 

The displacement value is defined as the number of parts of suppository ingredients that displace one gram of cocoa butter base. These values are summerized in Table 9.1. The following examples will illustrate the displacement value calculations ... 

In this problem, the active ingredient, zinc oxide, is prescribed as a percentage. If the displacement value is used and the cocoa butter amount is varied, the zinc oxide percent will not be 30%. Therefore, in situations like this, prepare a 30% zinc oxide - cocoa butter mixture and fill in the molds to obtain the desired suppositories. There is no need to vary the cocoa butter amount. 

H. Suppositories Solid preparations which melt at body temperature delivering medication for at-site treatment or for absorption at that point (usually rectal, vaginal, or urethral). Excipients include cocoa butter, waxy fatty acids, and derivatives, polyethylene glycol, theobroma oil, as well as many ingredients found in G. 

Cocoa butter-based suppositories can be prepared manually by pharmacists by mixing the ingredients to a pliable consistency in a mortar. 

Mineral oil is used primarily as an excipient in topical pharmaceutical formulations, where its emollient properties are exploited as an ingredient in ointment bases see Table I. It is additionally used in oil-in-water emulsions,as a solvent, and as a lubricant in capsule and tablet formulations, and to a limited extent as a mold-release agent for cocoa butter suppositories. It has also been used in the preparation of microspheres. " ... 

The base used in the formulation of suppositories can often affect the rate of decomposition of the active ingredients. Aspirin decomposes in several polyoxyethylene glycols which are often incorporated into suppository bases. Degradation was shown to be due in part to transesterification, giving the decomposition products salicylic acid and acetylated polyethylene glycol. The rate of decomposition, which followed pseudo first-order kinetics, was considerably greater than when a fatty base such as cocoa butter was used. Analysis of commercial batches of 100 mg indometacin-polyethylene glycol... 

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