Vaginal administration

Suppositories and pessaries— These are preparations intended for either rectal or vaginal administration of drugs. They are formulated with a suitable base that melts at body temperature. 

Vaginal Administration. Though not a common one, some materials do have routine exposure by this route (spermicides, tampons, douches, and antibiotics, for example), and, therefore, must be evaluated for irritation and toxicity by this route. The older preferred models used rabbits and monkeys (Eckstein et al., 1969), but, more recently, a model that uses rats has been developed (Staab et al., 1987). McConnell (1973) clearly described the limitations, particularly of volume of test material, involved in such tests. 

Bonucci, E., Ballanti, P., Ramires, P.A., Richardson, J.L., and Benedetti, L.M., Prevention of ovariectomy osteopenia in rats after vaginal administration of Hyaff 11 microspheres containing salmon calcitonin, Calcif. Tissue Int., 56 274-279 (1995). 

Pharmacokinetics Extent of systemic absorption after vaginal administration may be dependent on presence of a uterus 5%-8% in women who had a hysterectomy versus 12%-16% in nonhysterectomized women. 

All available dopamine agonists are active as oral preparations, and all are eliminated by metabolism. They can also be absorbed systemically after vaginal insertion of tablets. Cabergoline, with a half-life of approximately 65 hours, has the longest duration of action. Quinagolide has a half-life of about 20 hours, whereas the half-life of bromocriptine is about 7 hours. After vaginal administration, serum levels peak more slowly. 

Intrauterine infusion (intra-amniotic or extra-amniotic) has been reported to be associated with fewer gastrointestinal symptoms and less fever than parenteral or intra-vaginal administration (122). In intra-amniotic use, the puncture must be guided by ultrasonography, and before injection a control aspiration of some amnio tic fluid is required in order to avoid intrauterine or intravascular injection. Uterine rupture has been described with intra-amniotic treatment. 

Hamoda H, Ashok PW, Flett GM, Templeton A. A randomized controlled comparison of sublingual and vaginal administration of misoprostol for cervical priming before first-trimester surgical abortion. Am J Obstet Gynecol 2004 190 55-9. 

As early as 1978, the vaginal administration of steroids for contraceptive purposes was attempted, at that time using vaginal rings containing medroxyprogesterone acetate or... 

Coutinho EM, Silva AR, Carreira C, Barbosa I. Ovulation inhibition following vaginal administration of pills containing norethindrone and mestranol. Contraception 1984 29(2) 197-202. 

Systemic iodine absorption can occur after intravaginal administration of povidone-iodine (11). There were increases in serum iodine, protein-bound iodine, and inorganic iodine, but not serum thyroxine, after a 2-minute vaginal administration of povidone-iodine in non-preg-nant women (12). 

Softgel capsules have gained popularity and use in the pharmaceutical industry for human and veterinary use, as an oral dosage form, as suppositories for rectal and vaginal administration, single... 

Mizutani, T., et al. 1995. Danazol concentrations in ovary, uterus, and serum and their effect on the hypothalamic-pituitary-ovarian axis during vaginal administration of danazol suppository. Fertil Steril 63 1184. 

The ripening action of dehydroepiandrosterone sulfate after vaginal administration of a pessary and intravenous injections was found to be comparable [28]. 

Microparticulate systems present the advantage, in comparison with single-unit solid systems, to guarantee a wider contact area between the drug and the mucosa. Different microparticulate systems intended for vaginal administration were developed they include liposomes, microcapsules, and microspheres. Such systems can possess intrinsic bioadhesive properties or can be loaded in a vehicle with bioadhesive properties. 

Different drug delivery systems have been proposed for vaginal delivery of peptides and proteins. The first one was a mucoadhesive gel based on polyacrylic acid intended for vaginal administration of insulin [96]. More recently, microparticulate systems such as starch and hyaluronan ester (HYAFF) microspheres have been proposed for vaginal delivery of insulin... 

Ceschel, G.C., et al. 2001. Development of a mucoadhesive dosage form for vaginal administration. Drug Dev Ind Pharm 27 541. 

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