Pharmacotherapies for Women Only

Article excerpt

INTRODUCTION

The phrase women's health has appeared rather recently on the health-care scene in the United States. It has come not merely to imply concern with the diseases peculiar to women but also to imply an indictment of predominantly male-centered medical research that has slighted the majority gender. This circumstance has resulted in the Food & Drug Administration's altering of its requirements for drug development to include women as well as men in tests whenever both sexes are candidates for use of a medication.

The current aim of focusing attention on topics of concern to "women only" tends to limit the scope to therapy applied during the reproductive process and to the involved organs. But it also encompasses therapy of female hormone-modified conditions such as osteoporosis. Certainly qualifying also as being "for women only" are drug therapies taken during pregnancy and lactation.

MEDICATION EXPOSURE Drug exposure during pregnancy

The primary concern with use of drugs by pregnant women is the risk of fetotoxicity or teratogenesis. The former term implies an action that would result in death of the fetus, while the latter implies adverse modifications of development of the fetus that would result in birth defects. These generally, but not always, can be compatible with postuterine survival. For the sake of such concerns, a general guideline is to strive to avoid medication exposure during pregnancy as much as possible, permitting only urgently needed pharmacotherapies. A 1997 survey in the Southern Medical Journal showed that overthe-counter medications accounted for 54% of the total products taken during pregnancy by women delivering at the hospital surveyed. Medicines most commonly used in pregnancy were vitamins, calcium and iron products, analgesics, and antibiotics.

A list of known human teratogens, all consisting of prescription medications, is provided in Table 1. Some of the most clear-cut of teratogens are the antineoplastic agents; not all of the anticancer agents considered teratogenic have been listed in the table. It is no surprise that the embryonic and fetal developmental processes are susceptible to injury by the drastic biochemical or subcellular structural derangements that comprise the cytotoxic mechanisms of the antineoplastics. Some of the early (1 950s) cases of teratogenesis by antineoplastics were results of antifolate agents having been used unsuccessfully to induce abortion. Obviously, there is a serious problem when a pregnant woman is found to be in need of therapy with an antineoplastic.

Some other teratogenic drugs are antibacterials, which also can inhibit biochemical pathways and thus be injurious to an embryo or a fetus. Others are sex hormones, which can do harm prenatally that may be evident at birth as alteration of the development of genital organs in both sexes or may be manifest only much later in life. Exemplifying this is the increased risk of vaginal cancer in women exposed prenatally, during the mid-century decades, to a synthetic estrogen, diethylstilbestrol.

Necessary phamacotherapy during gestation

The antiepileptic drugs, for which continuous chronic intake is essential, include leading examples of teratogens. All of the commonly prescribed anticonvulsants are at least suspected of being teratogens. The fetal hydantoin syndrome (a phrase coined in parallel to fetal alcohol syndrome) has been described as including craniofacial anomalies, prenatal and postnatal growth deficits, mental retardation, and limb defects. Less frequently, there may be microcephaly and/or ocular, cardiac, or other organ defects.

There is evidence that the antiepileptics' mechanism for these effects depends upon the formation of oxidative metabolites-specifically, highly reactive epoxides, which react covalently with embryonic or fetal nucleic acids. Thus, the action of such metabolites is like that of antineoplastic agents of the alkylating group, which has included some epoxide-forming compounds. …