Suppository base

Suppository bases pharmaceutical bases that are solid at room temperature but melt at body temperature. 

For most purposes, it is convenient to classify suppository bases according to their physical characteristics into two main categories and a third miscellaneous group (i) fatty or oleaginous bases (ii) water-soluble or water-miscible bases, and (iii) miscellaneous bases, general combinations of lipophilic and hydrophilic substances (43). Appendix V presents a survey of commercial pharmaceutical suppositories and the respective suppository bases. 

The use of water-soluble bases may result in some irritation because, as they take up water and dissolve, they may produce slight dehydration of the rectal mucosa. They are widely used, however, and release the drug by dissolving and mixing with the aqueous body fluids. PEG suppository bases and glycerinated gelatin are the most popular in this class. 

Te Wierik GH, Eissens AC, Lerk CF. Preparation, characterization, and pharmaceutical application of lineardextrins. III. Drug release from fatty suppository bases containing amylodextrin. Pharm Res 1994 11(1) 108 110. 

Celebi N, Iscanoglu M, Degim T. The release of naproxen in fatty suppository bases by beta-cyclodextrin complexation. Pharmazie 1991 46(12) 863-865. 

Schmitt M, Guentert TW. Influence of the hydrophilicity of suppository bases on rectal absorption of carprofen, a lipophilic nonsteroidal anti-inflammatory drug. J Pharm Sci 1990 79(4) 359-363. 

Asikoglu M, Ertan G, Cosar G. The release of isoconazole nitrate from different suppository bases in-vitro dissolution, physicochemical and microbiological studies. J Pharm Pharmacol 1995 47(9) 713-716. 

Indication Active ingredient Product name Suppository base... 

Topical bioavailability can be improved by the enhanced release of a drug from ointment or suppository bases. 

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. 

Hardy, J.G., et al. 1987. The application of gamma-scintigraphy for the evaluation of the relative spreading of suppository bases in rectal hard gelatin capsules. Int J Pharm 38 103. 

Sugito, K., et al. 1988. The spreading of radiolabelled fatty suppository bases in human rectum. Int J Pharm 47 157. 

The complexation of drugs with CyDs can improve the chemical stability in suppository bases and bioconversion of the drugs to pharmacologically inactive metabolites in the rectum. 

Frijlink, H.W., A.J.M. Schoonen, and C.F. Lerk. 1980. The cyclodextrins on drug release from fatty suppository bases. In-vitro observations, ed. H.W. Frijlink, 77. Groningen Drukkerij van denderen. 

Takahashi, T., et al. 1986. Stabilization of AD-1590, a non-steroidal antiinflammatory agent, in suppository bases by (3-cyclodextrin complexation. Chem Pharm Bull 34 1770. 

Morgan, D.J., et al. 1992. Prolonged release of morphine alkaloid from a lipophilic suppository base in vitro and in vivo. Int J Clin Pharmacol Ther Toxicol 30 576. 

A vaginal suppository based on bromocriptine was employed for the therapy of hyperprolactinemia [32]. The rationale of the local vaginal delivery of bromocriptine lies in the noteworthy side effects consequent to oral therapy gastrointestinal disorders, extensive hepatic degradation, and hypotension. The pessary based on bromocriptine proved to be effective in lowering serum prolactin to normal levels after 20 days of local therapy the treatment was well tolerated by the majority of the patients and a minimal vaginal irritation was observed. 

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]. 

Fractionated palm oil is a solid obtained by fractionation and hydrogenation and is used as a suppository base... 

Theobroma Theobroma cacao (Sterculiaceae) kernel 35-50 oleic (35), stearic (35), palmitic (26), linoleic (3) suppository base, chocolate manufacture Theobroma oil (cocoa butter) is a solid... 

Cocoa seeds contain 35-50% of oil (cocoa butter or theobroma oil), 1-4% theobromine and 0.2-0.5% caffeine, plus tannins and volatile oils. During fermentation and roasting, most of the theobromine from the kernel passes into the husk, which thus provides a convenient source of the alkaloid. Theobroma oil or cocoa butter is obtained by hot expression from the ground seeds as a whitish solid with a mild chocolate taste. It is a valuable formulation aid in pharmacy where it is used as a suppository base. It contains glycerides of oleic (35%), stearic (35%), palmitic (26%), and linoleic (3%) acids (see page 44). 

Pharmaceutical grade poly(ethylene glycols) are poly(ethylene oxides) with terminal hydroxyl groups and have been approved by the E.D.A. and listed in both the United States Pharmacopoeia and Martindale under Macrogols for use as ointment and suppository bases (4J. Poly(ethylene glycol) can be chemically cross-linked retaining the hydrophilic nature of the PEO backbone in an infinite hydrogel network which will imbibe water and swell but not... 

Simon, K., Siiverkriip, R. 1995. Comparison of recent techniques to characterize the crystallization behaviour of fatty suppository bases. Thermochim. Acta 248, 271-287. 

A rigid bottle, a collapsible tube, or a flexible pouch made of plastic material may be used for liquid-based topical product. These preparations are marketed in a single- or multiple-unit container. For example, dissolved drug (or any substance, e.g., benzocaine) may diffuse in the suppository base and can, for instance, partition into polyethylene linings of the suppository wrap. 

PEG —O—, —OH Plasticizer, solvent, suppository base, tablet and capsule lubricant... 

Among newly developed colon-specific drug delivery systems, pressure-controlled delivery capsules (PCDCs) [161] can be mentioned. Their mechanism of action is based on the relatively strong peristaltic waves taking place in the colon and leading to an increased luminal pressure. They consist of a capsular-shaped suppositories coated with a water-insoluble polymer (ethyl cellulose). Once taken orally, PCDCs behave like an ethyl cellulose balloon, because the suppository base liquefies at body temperature. In the upper GI tract, PCDCs are not directly subjected to the luminal pressures since sufficient fluid is present in the stomach and small intestine. The reabsorption of water in the colon provokes an increase of the luminal content viscosity. As a result, increased intestinal pressures directly affect the system via colonic peristalsis. Consequently, PCDCs mpture and drug release in the colon take place. 

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