Suppositories

SUPPOSITORIES (Latin suppositoria) (FUI), inserts, suppositories; a medicinal form intended for introducing medicinal substances into body cavities or (less frequently) into wounds, where they melt or dissolve. Chemically, suppositories are similar to ointments: they represent emulsions or suspensions, and sometimes solutions of medicinal substances in bases; however, the bases must be sufficiently solid at room temperature so that the suppository can be inserted into a body cavity without deformation. The best base for suppositories is cocoa butter (see). In recent times, imported cocoa butter has been replaced by hydrogenated sunflower or cottonseed oil or various fat alloys with wax and paraffin. These alloys must be plastic, sufficiently hard at room temperature, and have a melting point not higher than 36°C. Suppositories are divided by purpose and form into: 1) candles-for introduction into the rectum. These candles are given the shape of a cylinder ending in a cone (shape of a bullet) or a cone; 2) balls (globuli)-for introduction into the vaginal cavity (see Vaginal balls). The usual form is spherical, oval, or egg-shaped (ovuli), sometimes flattened almond-shaped; 3) sticks-see Bacilli medicati. The mass for suppositories is prepared by mixing the medicinal substance with the ground base and subsequent rolling to obtain the required shape. Mechanical formation of suppositories is done with suppository presses-machines for extruding rods or finished candles. Suppositories are also formed by hand. As a water-soluble base for suppositories, dense jellies with a melting point not higher than 37°C are also used. Such a jelly is prepared, for example, from gelatin, from agar-agar (1 part agar-agar, 2 parts glycerin and 7 parts water; some varieties of agar-agar give a jelly even with a larger amount of liquid). Soap-glycerin jelly serves as the material for glycerin (laxative) suppositories; the mass for these according to F VII is prepared by dissolving at heating on a water bath 3 parts of crystalline sodium carbonate salt in 60 parts of glycerin, after which 5 parts of stearic acid (pure stearin) are gradually added, and after the evolution of carbon dioxide and disappearance of foam, the mass is poured into molds with such calculation that each candle contains 3 z of glycerin (i.e. 3.3 g of mass). Medicinal substances are usually added to jellies in the form of water-soluble compounds, since these masses, unlike cocoa butter, are not formed in mortars and machines, but only by pouring into appropriate molds. From 1.0 to 4.0 g of base is taken per candle; in pharmaceutical practice, it is customary to prepare candles weighing 2.0 g each; balls are prepared in the same way, but are given the shape of balls weighing from 2.0 to 4.0 g; the latter weight is recommended by F VII if there are no special instructions from the physician. Sticks are usually prepared according to individual prescriptions, with the physician usually indicating the weight and thickness of each stick or the length and thickness of the stick, leaving it to the pharmacist to calculate the required amount of base. Suppositories undergo relatively rapid spoilage under the influence of microorganisms. Therefore, observance of possible asepsis during their preparation is recommended; for suppositories prepared in reserve, it is recommended to mix medicinal substances with preservatives. Due to the absorption of the components of suppositories, attention must be paid to the fact that the amounts of potent or poisonous substances prescribed in their composition do not exceed the maximum (highest) doses allowed by FUI. Along with the described forms, various hollow suppositories were also previously used. For these forms, hollow molds were prepared from cocoa butter; the medicinal substance was placed in this cavity and the opening was sealed with a cork of cocoa butter or a drop of melted cocoa butter. Such are the Boas suppositories, filled with glycerin. Sticks for introduction into the urethra (urethral suppositories) were sometimes prepared on rods made of thin, flexible, and smooth wire (Anthrophora), which facilitated the introduction of the stick deep into the canal; after the suppository melted, the wire was easily extracted from the urethra. In the form of suppositories, all kinds of medicinal substances can be prescribed. Most commonly used are candles with narcotics (Extr. Belladonnae, Extr. Opii), mild antiseptics (Ichthyol, Bals. peruvianum, Zinc. oxydat., compounds of bismuth, Jodoform, etc.), astringent substances (Tannin, various plant extracts, especially in hemorrhoidal suppositories), and others. As laxatives, suppositories with glycerin or soap are used. The composition of Globuli and their purpose-see Vaginal balls, the composition and purpose of sticks-see Bacilli medicati.