Rectal preparations

Tiaprofenic acid is a racemate and given as oral or rectal preparations (600 mg/day) and as an intramuscular injection of the trometamol salt. 

Enema A rectal preparation for therapeutic, diagnostic, or nutritive purposes. 

Included in the FDA Inactive Ingredients Guide (ophthalmic preparations, oral capsules and tablets, otic and rectal preparations, topical aerosols, creams, emulsions, ointments and solutions, and vaginal preparations). Included in nonpar-enteral medicines licensed in the UK. Included in the Canadian List of Acceptable Non-medicinal Ingredients. 

Cetyl alcohol is mainly used in topical formulations, although it has also been used in oral and rectal preparations. 

Included in the FDA Inactive Ingredients Guide (oral solutions and suspensions rectal preparations). Included in the Canadian List of Acceptable Non-medicinal Ingredients. 

Polyethylene glycols (PEGs) are widely used in a variety of pharmaceutical formulations including parenteral, topical, ophthalmic, oral, and rectal preparations. It has been used experimentally in biodegradable polymeric matrices used in controlled-release systems. 

One case report indicates that clarithromycin may enhance the effects of inhaled budesonide and although the authors suggest that prolonged use of clarithromycin and the terminal condition of the patient may have been factors, they advise close monitoring if the combination is used. Note that rectal budesonide produces higher plasma levels than the oral or inhaled use. The manufacturers of one UK rectal preparation advise that potent inhibitors of CYP3A4 (they name clarithromycin) should be avoided. However, given the evidence available, this seems a very cautious approach. 

FDA approved for topical, vaginal, and rectal preparations. Included in nonparenteral medicines licensed in the United Kingdom... 

An intramuscular injection with a licensed pharmaceutical preparation that contains hydrocortisone sodium succinate would constitute a major treatment option. However, the child s parents do not want to give an injection to their child. Klaartje drinks very reluctantly as all babies with the Trader Willi syndrome. The parents don t consider administration with the feeding of the contents of a capsule or of crushed tablets as a reliable option. Therefore, the doctor has suggested a rectal preparation. 

Rectal preparations are intended for rectal use in order to obtain a systemic or local effect, or they may be intended for diagnostic purposes. 

The Ph. Eur. lists under Rectal preparations or Rectalia the following dosage forms ... 

SemisoUd rectal preparations (ointments, creams and gels)... 

Microbiological stability may be a problem too. Aqueous enemas are prone to microbiological contamination and growth. The Ph. Eur. sets the same requirements for TAMC and TYMC (see Sect. 19.6.3) to rectal preparations as to oral preparations (10 CFU/g or mL, see Sect. 19.6.2). Enemas, like oral mixtures, should also meet with the requirements of preservation efficacy. For preservatives reference is made to Sect. 23.8. Generally methyl parahydroxybenzoate 0.15 % is used. 

Containers for liquid rectal preparations range in volume from several millilitres to approximately 100 mL. The container must be equipped with a rectal cannula to administer the enema. Enemas can be packaged in enema bags (see Sect. 24.4.13.2). These have a longer cannula with which the enema can be administered deeper into the rectum. Another possibility is to package an enema in a syringe on which a rectal cannula is placed (see Sect. 24.4.16). 

Administration of liquid rectal preparations requires a squeezable bottle (see Sect. 24.4.4.1), a bag (Sect. 24.4.13.2) or a syringe (see Sect. 24.4.16), with a rectal cannula (see Fig. 24.10). This cannula is preferably of flexible material to prevent damage to the rectal mucosa. This is less important with short cannulas than with long ones. An enema bag has a long flexible tube cannula. This cannula should be lubricated or should be made of slippery material to ease insertion. The cannula should have a rubber one-way check valve when respiration is possible (with enema bottles, not with enema bags). 

With respect to dosage forms such as oral preparations, rectal preparations and preparations for cutaneous application the Ph. Eur. states that during the development it must be demonstrated that the nominal volume or content can be obtained from the container.. 

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