Vaginal solutions sterility

Just as in enemas (see Sect. 11.9.6) chemical stability may be a problem in vaginal solutions. This caimotbe avoided by choosing a different pH or another solvent as with enemas. So the active substance should be inherently stable in water. For the microbiological stabiUty of non-sterile vaginal solutions which are often concentrates for multiple dosing, preservation may be necessary if the concentrate doesn t meet the test on preservation effectiveness (see Sect. 32.8). Methyl parahydroxybenzoate can be used as a preservative. 

Non-sterile but preserved vaginal solutions may have a shelf life of 3 years after preparatiOTi, if prepared according to a standard formula and chemically and physically stable. Once opened by the patient, such vaginal solutions can be assigned an in-use period of 6 months. A concentrate diluted by the patient should be kept only 24 h after dilution. A non-standardised preserved preparatirai should not be stored in the pharmacy because the maximal shelf Ufe of say 1 month, may be reasonably needed by the patient. A diluted concentrate may be kept for 24 h after dilution. Unpreserved n(Mi-sterile vaginal solutions may have a shelf life of maximal 2 weeks and they have to be stored in a refrigerator. 

Sterile vaginal solutions are packaged in a single-dose container that can be sterilised, for instance glass (preferably class I, eventually class II) or plastic (polypropylene). Preserved concentrates, intended to be diluted before use, are usually packaged in a container of glass (class III) or plastic (polypropylene, polyethylene) meant for multiple dosing. 

Method of preparation, release control and quality requirements of sterile vaginal solutions are the same as for irrigation solutions (Preparations for irrigation Ph. Eur., see Sect. 14.7). Preparation method and release controls of non-sterile vaginal solutions are the same as for solutions for cutaneous use (see Sect. 12.6.5). 

Eye lotions (irrigations for the eye) are discussed in Sect. 10.6.2. Vaginal solutions that don t need to be sterile are discussed in Sect. 11.12. Whole bowel irrigations are used before diagnostic examination. Those solutions for oral or rectal use are not described in this chapter. 

Cicinelli, E., Cignarelli, M., Sabatelli, S., Romano, F., Schonauer, L. M., Padovano, R., and Einer-Jensen, N. (1998), Plasma concentrations of progesterone are higher in the uterine artery than in the radial artery after vaginal administration of micronized progesterone in an oil-based solution to postmenopausal women, Fertil. Steril., 69, 471—473. 

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