ABSTRACT
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Recent years have witnessed an increased interest in delivering drugs to the vagina and
uterus. Much of this interest has stemmed from new perspectives on a range of female health
applications, including contraception, hormone replacement therapy (HRT), cervicovaginal
cancer, and the prevention and treatment of sexually transmitted diseases (STDs). Typically,
these clinical applications take advantage of vaginal administration for provision of a direct
local effect within the vaginal fluid or vaginal tissue. Consequently, systemic side effects are
minimized and the magnitude of the dose may be much reduced compared to more
conventional routes of drug delivery. However, employing the vagina as a portal for the
systemic absorption of drugs, such as is required for steroidal contraception, has also been
shown to be useful, particularly for drug molecules that undergo extensive first-pass hepatic
metabolism. The renewed interest in vaginal drug delivery has also prompted reexamination
of the anatomy, physiology, histology, and immunology of the vagina and uterus, leading to
a much better understanding of the key parameters and mechanisms influencing vaginal drug
absorption. This is best exemplified by the developments in the fields of uterine targeting,
microbicides for HIV prevention, and vaginal vaccinations. It is, therefore, the purpose of this
chapter to describe the various concepts and review recent advances in the use (and potential
use) of the vagina and the uterus for the absorption of drug substances. The term absorption is
interpreted in its widest sense so as to cover both local tissue and systemic absorption.
