Suppository bases additives

The physicochemical properties of the drug molecules and the formulation can also influence rectal drug absorption (Table 7.1). Crucial parameters in this regard include drug concentration, molecular weight, solubility, lipophilicity, pKa, surface properties, and particle size [12]. In addition, formulation properties such as the nature of the suppository base material may play a critical role in regulating drug absorption. 

A vaginal suppository based on ornidazole, a drug characterized by the activity against bacteria and protozoa, demonstrated the same safety and effectiveness in the treatment of vaginitis as that of a tablet formulation in addition, the slippery and smooth surface of the suppository-facilitated application and the irritation in the vulva-vaginal region was reduced in comparison with that induced by the tablet formulation [33]. 

Surface-active agents are widely used in combination with other suppository bases. The inclusion of these agents in the formulation may improve the wetting and water-absorption properties of the suppository. In addition, emulsifying surfactants help to keep insoluble substances suspended in a fatty base suppository,... 

Whitworth CW, Pongpaibul Y. The influence of some additives on the stability of aspirin in an oleaginous suppository base. Can J Pharm... 

In addition, anionic emulsifying wax (10%) has been added to theobroma oil to produce a suppository base with a melting point of 34°C. 

Polymers and biopolymers can not only be active substances but also preparation bases (e.g. ointment and suppository bases), stabilizing additives in emulsions and suspensions, fillers, binders, disintegrants, lubricants, and gli-dants in tablet preparation. Coating polymers lead us to a major field of modern pharmaceutical technology, which is controlling the release or dissolution of active substances. 

Seldom will a suppository base meet all these qualities. The properties of a base may be improved by the addition of a substance that influences the melting point. For instance. 

Cosmetics and Pharmaceuticals. The main use of hexadecanol (cetyl alcohol) is in cosmetics (qv) and pharmaceuticals (qv), where it and octadecanol (stearyl alcohol) are used extensively as emoUient additives and as bases for creams, Hpsticks, ointments, and suppositories. Octadecenol (oleyl alcohol) is also widely used (47), as are the nonlinear alcohols. The compatibiHty of heavy cut alcohols and other cosmetic materials or active dmg agents, their mildness, skin feel, and low toxicity have made them the preferred materials for these appHcations. Higher alcohols and their derivatives are used in conditioning shampoos, in other personal care products, and in ingested materials such as vitamins (qv) and sustained release tablets (see Controlled RELEASE technology). 

Hakata, T. Ijima, M. Kimura, S. Sato, H. Watanabe, Y. Matsumoto, M. Effects of bases and additives on release of carbon dioxide from effervescent suppositories. Chem. Pharm. Bull. 1993, 41, 351-356. 

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. " ... 

Additives Some grades of commercial bases already contain additives, and these are usually identified by the manufacturers by means of suitable letters and numbers. Additives may also be incorporated by formulators. Properties of suppositories that have been modified and additives or types of additives that have been used are shown in Table I. Water is undesirable as an additive because it enhances hydrolysis and... 

Certain fat-soluble medications, such as chloral hydrate, may depress the melting point when incorporated into a base. Similarly, when large amounts of an active substance, either solid or liquid, have to be dispersed into a base, the rheological characteristics of the resultant suppository may be changed, with concomitant effects on release and absorption. Careful selection of bases or the inclusion of additives may therefore be necessary. 

The bases of all products are likely to contribute an additional emollient and soothing effect, and the lubricating effect of suppositories may ease straining at stool. 

For the preparation of a solution suppository the macrogol base is melted, the active substance is dissolved in the melt and the mass is poured, without any additional step. Melting the base in a closed vessel on the water bath (see Sect. 11.7.1) fits better because the dispersion step is lacking. The closed vessel may be a medicine bottle or a squeeze bottle. The medicine bottle is to be preferred because no transfer of molten base is necessary (no loss), it is transparent for controlling the dissolution process and it is suitable for pouring as there is no suspension to be kept homogeneous. The squeeze bottle is less preferred because it is not transparent. 

Here a copy of the batch preparation record of the diclofenac sodium 12.5 mg suppositories could be included in the product file. Additional information may be given to explain the reasons for the choice of the excipients, the melting temperature of the hard fat base, the choice of the preparation method, the determination of overages, and of the number of suppositories that are expected to be rejected during production, etcetera. 

Africa, where the sample in which the relevant strain had been discovered was taken. Pimaricin has been used as a vaginal suppository for the therapy of Candida infections and for other medical purposes like ophthalmic suspensions (Raab, 1972). Since the early 1960 s efforts have also been made to introduce it as a food preservative. Also in this case it has achieved a certain importance especially in the surface preservation of cheeses. Due to the currently increasing world-wide concern about the resistance of pathogenic bacteria against antibiotics it is discussed whether antibiotics used in food should be banned or its usage should be more restricted in the future. The addition of preparations containing pimaricin to cheese coatings based on polymer emulsions is still an important application in this industrial sector. 

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