Vaginal dosage forms

Both for local and systemic therapy to prevent poor retention, messiness, and leakage associated with conventional vaginal dosage forms, it is useful and sometimes necessary to prolong and improve the contact between the drug and the mucosa. The presence of mucoadhesive agents in the formulation could enable the attainment of such a goal. 

These factors become particularly important for preparations intended for long-term vaginal administration. Formulation factors which affect vaginal drug delivery which are common to the various types of vaginal dosage forms include ... 

Several publications have examined the many types of vaginal delivery systems already marketed or under development. " In the development of vaginal dosage forms, the following considerations should be addressed ... 

Cabergoline is commercially available as 0.5-mg oral tablets. The initial dose of cabergoline for the treatment of hyperprolactinemia is 0.5 mg once weekly or in divided doses twice weekly. This dose may be increased by increments of 0.5 mg at 4-week intervals based on serum prolactin concentrations. The usual dose is 1 to 2 mg weekly however, doses as high as 4.5 mg weekly have been used. Recent studies have also evaluated the efficacy of a vaginal dosage form of cabergoline to reduce the adverse effects associated with oral therapy. ... 

Rectal dosage forms may be applied for systemic as well as for local action. Vaginal dosage forms are almost exclusively used for local action. Rectal administration of an active substance for systemic action is sometimes a good... 

Vaginal foams Medicated vaginal tampons From the rectal dosage forms the suppositories, enemas, ointments and creams are important as extemporaneous pharmacy preparations from the vaginal dosage forms fliese are the vaginal suppositories (pessaries), solutions, creams and gels. 

In contrast, very little is known about the biopharmaceutics of vaginal dosage forms. The vagina has good absorbing properties, but this is seldom used for a systemic effect. Vaginal dosage forms are administered for a local effect only. 

Rectal and vaginal dosage forms aimed to obtain a local effect are, from a biopharmaceutical viewpoint, comparable with dermal preparations. However it should be known that after rectal and vaginal application a greater part of the active substance may reach the general circulation than after cutaneous application. This may result in significant blood levels and unwanted systemic effects. 

A good adhesion of the base to the vaginal mucosa is needed, because a vaginal dosage form may easily be lost due to the absence of a sphincter. Little is known about the adhesion properties of suppository bases, because for rectal... 

Only a dissolved active substance can be absorbed in the bloodstream. To be able to dissolve the active substance first has to be released from the pharmaceutical form. The disintegration of oral dosage forms such as capsules and tablets and the disintegration of rectal and vaginal dosage forms such as suppositories are therefore important pharmaceutical parameters for the effectiveness of the medicine. 

Aerosols. Pressurized containers to deHver aerosolized dmg products through appropriate systems of valves and actuators have been available since the 1950s (see Aerosols). Such dosage forms are used as external appHcations of lotions and creams, for oral inhalation, or for treatment of the vaginal cavity, eg, contraceptive foams. Aerosols contain two- or three-phase systems, wherein a volatile Hquid or admixture of Hquids is sealed in a... 

The inclusion of the a routine microbial limit test in a marketed product stability protocol depends on the pharmaceutical dosage form. Typically, the test would be used only for nonsterile products, especially oral liquids, nasal sprays, and topical liquids, lotions, and creams that have sufficient water activity to support the growth of microorganisms. In contrast, tablets, powder- and liquid-filled capsules, topical ointments, vaginal and rectal suppositories, nonaqueous liquids and inhalation aerosols with a water activity too low to allow for the product to support the growth of microorganisms would not be routinely tested. 

Compendia that describe excipients used for various formulations such as parent-erals, vaginal formulations, and antibiotics are offered in a number of publications (7-9). The FDA publishes on its internet site, www.fda.gov, the downloadable Inactive Ingredient Database. The components of proprietary inactive ingredients are not always included. All inactive ingredients that are present in currently approved final dosage form in drug products are listed. Whenever included, one may need to search for such data under individual component entries. 

Suppositories are pharmaceutical dosage forms intended for administration of medicine via the rectum, vagina, or urethra that melt, soften, or dissolve in the body cavity. Rectal and vaginal suppositories are most common but urethral suppositories are sometimes used. Suppositories are indicated for administering drugs to infants and small children, severely debilitated patients, those who cannot take medications orally, and those for whom the parenteral route might be unsuitable. Suppositories are used to administer drugs for either systemic or local application. Local applications include the... 

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... 

How the product will be used by the patient or the customer—Here again our industry is so diverse that we must indicate that the limits calculated should take into account the nature of the customer. Is the customer another company that uses the product, which may be a chemical, to make another intermediate, or is the customer the patient who actually takes the product in the form of a finished pharmaceutical dosage form Is the product a sterile product and do we need to consider bacteria as a potential contaminant or is the product a nonsterile product in which bacterial contamination may be a lesser issue If the product is a finished pharmaceutical dosage form, will it be used intravenously, orally, ophthalmically, topically, rectally, vaginally, or by other means ... 

Is a local or systemic effect required This will influence, for example, the choice between a traditional dosage form, such as a semisolid cream or gel, and a system that promotes increased intravaginal residence, with a concomitant increased possibility of absorption across vaginal epithelium, for example, from intravaginal ring (IVR) systems or systems utilizing a bioadhesive polymer component. 

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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