الفهرس 
Title : A Pharmaceutical Study on Certain Vaginal Drug Delivery Systems
ContentOnly 14 pages are availabe for public view
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Abstract
The human vagina is a fibromuscular collapsed canal that is structurally described as S in shape and runs from the lower portion of the uterine cervix to the outer portion of the vulva known as the labia minor. It has a length of approximately 7–10 cm, a breadth of more than 4 cm, and a thickness of 150–200 mm. Endopelvic fascia and ligaments hold the vagina in place at a 90-degree angle to the uterus. Histologically, the vaginal wall is made up of three main layers: muscular, tunica adventitia, and mucosa.
Due to its huge surface area, abundant blood supply, and permeability to a wide range of chemicals, the vagina was thought a promising site for the administration of locally acting medications and to be of considerable importance for systemic drug delivery, uterine targeting, or even vaccination. Simple diffusion is the most common permeation method for most chemicals, in which hydrophobic compounds are absorbed preferentially through the intracellular pathway. On the other hand, the paracellular pathway preferentially absorbs hydrophilic compounds through pores in the vaginal mucosa.
Commonly, vaginal dosage forms include vaginal suppositories or pessaries, vaginal tablets, foams, sprays, gels, creams, ointments, douches, and vaginal rings. Antifungal, antiprotozoal, antiviral, antibacterial, labor-inducing, spermicidal agents, cervical ripening agents, hormone replacement therapies, prostaglandins, and steroids have all been delivered through the vaginal cavity.
Spermicides are chemical barrier contraceptives that are utilized before sexual activities to prevent pregnancy. The fundamental spermicidal action is attributed to its ability to disrupt the sperm plasma membrane, to avoid sperm-egg interaction. They include surfactants/bactericides, membrane stabilizing compounds, sulfhydryl binding drugs, natural products, and synthetic products. Modern spermicides are fabricated in a variety of dosage forms including gels, foams, creams, suppositories, pessaries, capsules, foaming tablets, and melting films. They show several merits as safe, available, easy to use, woman-controlled methods, effectively prevent pregnancy, if used correctly with every intercourse, can be inserted as much as 1 hour before intercourse, no hormonal side-effects, no effect on breast milk, discontinuation at any time, may increase lubrication, can be used immediately after childbirth.
Nonoxynol-9 (N-9) is a typical surfactant. It has been successfully discovered as a locally acting vaginal spermicide. It comes into several formulations such as creams, gels, foams, and condom lubricants. The main disadvantage of N-9 is its detergent-type action that can change vaginal normal flora and cause vaginal irritation as well as genital irritation in a male partner.
Propranolol hydrochloride (PNL) is known as a β-adrenergic blocker that is commonly utilized to treat tremors, angina, hypertension, and other cardiac rhythm disorders. It also has membrane stabilizing properties that can inhibit human sperm motility. Further, both α and β‐adrenergic receptors have been discovered on sperm cells that can be blocked by PNL interfering with sperm mobility, resulting in spermicidal action.
Nanocarriers (NC) are colloidal drug delivery systems with particles that are less than one micron in size. They can change the basic characteristics and bioactivity of medications due to their large surface area to volume ratio. Some of the advantages of employing NC as a drug delivery system include enhanced pharmacokinetics, bio-distribution, lower toxicities, improved solubility, stability, controlled release, and site-specific delivery of therapeutic compounds. They involve polymeric nanocarriers, liposomes, dendrimers, nano-emulsions, nanofibers, and inorganic.