Dear Rishabh,

The following publications describe methods for drug release from vaginal suppositories:

1-J Drug Target. 2003 Apr;11(3):177-85.

In-vitro evaluation and vaginal absorption of metronidazole suppositories in rabbits.

Ozyazici M1, Turgut EH, Taner MS, Köseoglu K, Ertan G.

Author information

Abstract

Vaginal suppository formulations of metronidazole were prepared using six different bases as Witepsol H15, Cremao, Ovucire WL2944, Ovucire WL3264, PEG 1500, PEG 6000. Three different dissolution methods were used to evaluate the in vitro drug release from the suppositories. The diffusion studies were performed through synthetic (cellophane) and natural membrane (rabbit vagina), but the drug did not show good permeation characteristics from natural membrane. Ovucire WL3264 suppositories of metronidazole labeled with 99mTc (Tecnetium-99m) were used for the vaginal absorption and biodistribution studies in the rabbits. Scintigraphic images were collected after vaginal administration of the labeled suppositories using SPECT gamma fitted with a low energy, high-resolution parallel hole collimator. The labeled drug showed high biodistribution in urine beside vaginal site. The results of this study suggested that the Ovucire WL3264 suppository of metronidazole prepared for vaginal infections could also be effective in the urinary infections.

http://www.ncbi.nlm.nih.gov/pubmed/14577974

2-METRONIDAZOLE BIOADHESIVE VAGINAL SUPPOSITORIES: FORMULATION, IN VITRO AND

IN VIVO EVALUATION

Research Article

HAIDY ABASS*1, RABAB KAMEL2, AHMED ABDELBARY3

1Department of Pharmaceutical Technology, Faculty of Pharmacy, German University in Cairo, El tagamoo El Khames Main Entrance Cairo,

Egypt, 2Department of Pharmaceutical Technology, National Research Center, Dokki, Cairo, Egypt, 3Department of pharmaceutics and

Industrial Pharmacy ,Faculty of Pharmacy ,Cairo University, Kasr El -Aini St., 11562, Cairo, Egypt. Email:[email protected]

Received: 29 Aug 2011, Revised and Accepted: 26 Nov 2011

ABSTRACT

Drug administration via mucosal membranes, including the vaginal, has the advantage of by passing the hepatogastrointestinal first pass metabolism associated with oral administration. Metronidazole suppositories were prepared using different suppository bases viz., water soluble bases ( PEGs and gelatin ) emulsion and fatty bases. The physicochemical properties of most of the prepared MTZ suppositories comply with the pharmacopoeial limits and passed the quality control tests. In general, water soluble suppository bases gave higher release than did the emulsion in citrate buffer pH 4. PEG base (F14), gelatin base (Fl8) and emulsion base (F23) gave the highest drug release and selected for further investigation. The release of MTZ from polyethylene glycol bases followed, first and Higuchi order release model, while gelatin and emulsion obeyed first model.

The tested suppository showed enhancement of drug absorption from tested suppository and the One way ANOVA analysis for AUC(0-∞) showed that the P value is 0.0502, considered not significant. The microbiological results showed that the bioadhesive formulae that released the concentration of 0.25 mg/ml of the drug and sustained this concentration for 120 min can be effective on C. albicans moreover bioavailability study was performed on flagyl ® vaginal suppository (market product) and the prepared pluronic127 –cp934 bioadhesive vaginal gel ,eight female rabbits were randomly divided into two groups, each containing four rabbits the results showed that the tested formulae did not exhibit enhancement in bioavailability in comparison to the market product which mean lower side effects and localized effect inside the vagina. 

http://www.ijppsjournal.com/Vol4Issue1/3014.pdf

3-Comparative bone uptake study of alendronate sodium from vaginal suppositories prepared with polyethylene glycol and massa estarinum bases

INTRODUCTION Bisphosphonates are used in the management of various disorders affecting the skeleton, includ- ing osteoporosis, metastatic bone disease and Pa- get’s disease of bone. Bisphosphonates are selec- tively uptake at active bone sites, suppressed the osteoblast and osteoclast mediated bone resorp- tion (1-4). Alendronate sodium (ALD) is a second generation amino bisphosphonates that selec- tively inhibits osteoclast-mediated bone resorp- tion, increases bone mineral density and reduces the incidence of vertebral, hip and other fractures (5-7). Like all bisphosphonates, ALD is poorly ab- sorbed from the gastrointestinal tract, with an oral bioavailability of around 0.9–1.8% (8). Its ab- sorption is markedly reduced by food (9). In recent years, there is a challenge for novel drug delivery systems to achieve improved bio- availability and safety. Various researchers have described new formulations to treat bone dis- ease with minimal side effects and high efficien- cy. Because of the poor gastrointestinal absorp- tion several administration routes have been at- tempted to enhance the bioavailability of bis- phosphonates like intravenous, subcutaneous and intramuscular injections (10-13). Also Asikoglu et al. have demonstrated rectal ab- sorption of ALD (14). The unique properties like rich blood supply and the large surface area makes vagina an important area for systemic drug delivery (15). The advan- ABSTRACT: The aim of this study was to compare the bone uptake of alendronate sodium (ALD) from vaginal suppositories prepared with massa estarinum AB (ME) and polyethylene glycol 1500 (PEG) bases. For this purpose, ALD was radiolabeled with 99mTecnetium Pertech- netate (99mTc) by direct method. Radiochemical purity and stability of 99mTc-ALD was per- formed with chromatographic studies. 99mTc-ALD containing suppositories were prepared with ME and PEG bases. Physical properties of suppositories were evaluated. The physico- chemical diffusion study was carried out to compare the release of ALD from different sup- pository bases. The bone uptake of 99mTc-ALD was observed by gamma scintigraphy stud- ies. 99mTc-ALD containing suppositories were administrated to rabbits via vaginal route. The scintigraphic images were obtained with a gamma camera at different time intervals up to 240 minutes. According to our studies, radiochemical purity of 99mTc-ALD was observed more than 95% up to 6 hours. At 240 minutes of physicochemical diffusion studies, released ALD has 0.620 ± 0.091 mm and 10.465 ± 0.651 mm diameter zone from ME and PEG base suppositories respectively. According to the gamma scintigraphy studies, although no bone uptake observed after ME suppositories application, rabbit’s bones were clearly visible after PEG suppositories applied. The results of physicochemical diffusion and gamma scintigra- phy studies were found compatible in each other. KEY WORDS: Alendronate sodium, bone uptake, vaginal suppository, massa estarinum, polyethylene glycol Comparative bone uptake study of alendronate sodium from vaginal suppositories prepared with polyethylene glycol and massa estarinum base

http://webcache.googleusercontent.com/search?q=cache:http://e-dergi.marmara.edu.tr/marupj/article/download/5000010843/5000010859

4- Formulation and in vitro study of antibacterial vaginal suppositories

ARTICLE in PHARMACEUTICA ACTA HELVETIAE 69(3):141-8 · JANUARY 1995 

Vaginal suppositories frequently used in gynaecological therapy were studied. Several antibacterial pharmacons are used for the topical treatment of vaginitis of various origins. In view of the fact that the liberation of the given active substance and the subsequent therapeutic effect may be improved or inhibited by the vehicle, our aim was to find the optimal suppository base for vaginal suppositories containing sulfadimidine, chloramphenicol and gentamicin sulfate by means of in vitro experiments. On the basis of breaking hardness, disintegration time and spreading properties the French Suppocire NA product, and compositions of macrogols with lower molecular weight proved to be the best lipophilic and hydrophilic bases, respectively. Among the lipophilic bases the in vitro drug liberation of Suppocire NA was significantly better (P < 0.05) than the other lipophilic bases. This vehicle is recommended for the topical treatment of vaginitis, as these suppositories have the further advantage that they can easily be produced on a magistral, galenical or industrial scale as well.

https://www.researchgate.net/publication/15353308_Formulation_and_in_vitro_study_of_antibacterial_vaginal_suppositories

Hoping this will be helpful,

Rafik

Article Formulation and in vitro study of antibacterial vaginal suppositories