Reproductive System Drugs Chapter 24 Reproductive System Drugs

Introduction Hormones that regulate reproductive system functions include endogenous chemical substances Originate within different areas of the body Reproductive hormones categories Gonadotropic Androgens Estrogens Progestins 2

Introduction (cont’d.) The following slides discuss various reproductive system drugs Refer to the chapter for specific side effects, contraindications, and interactions 3

Gonadotropics Gonadotropic hormones include: Follicle-stimulating hormone (FSH) Stimulates development of ovarian follicles in the female and sperm production in testes of the male Luteinizing hormone (LH) Works in conjunction with FSH to induce secretion of estrogen, ovulation, and development of corpus luteum 4

Gonadotropics (cont’d.) Luteotropic hormone (LTH) Stimulates secretion of progesterone by the corpus luteum and secretion of milk by the mammary gland 5

Androgens Male sex hormones Secreted mainly in the interstitial tissue of the testes in the male and secondarily in the adrenal glands of both sexes Inadequate production in the male may be due to pituitary malfunction or to atrophy, injury to, or removal of the testicles, resulting in eunuchism or eunuchoidism 6

Erectile Dysfunction Medications Inability to achieve or maintain an erection sufficient for satisfactory performance Incidence increases with age Nitric oxide: principal mediator in attaining and maintaining an erection Phosphodiesterase (PDE) inhibitors Block phosphodiesterase type 5, found in the corpus cavernosum Thought to impair the production of nitric oxide 7

Estrogens Female sex hormones Produced mainly by the ovary and secondarily by the adrenal glands Responsible for development of female secondary sexual characteristics Produce an environment suitable for fertilization, implantation, and nutrition of the early embryo Affect secretion of hormones FSH and LH from the anterior pituitary gland 8

Estrogens (cont’d.) Menopause Estrogen therapy (ET): estrogen alone Natural life event, or can be artificially induced Levels of estrogen and progesterone are reduced, leading to vasomotor symptoms and atrophic vaginitis Estrogen therapy (ET): estrogen alone Associated with increased risk of endometrial carcinoma in women with an intact uterus When progestin is combined with estrogen, the risk of endometrial cancer is substantially reduced 9

Progestins Progesterone Hormone secreted by the corpus luteum and adrenal glands Responsible for changes in uterine endometrium in the second half of the menstrual cycle Preparation for implantation, development of maternal placenta after implantation, and development of mammary glands Progestins are synthetic drugs that exert progesterone-like activity 10

Progestins (cont’d.) Contraceptive agents Suppress release of pituitary hormones, follicle-stimulating hormone (FSH), and luteinizing hormone (LH) Results in ovulation prevention Progestin-only contraceptives Prevent pregnancy by inhibiting ovulation, changing cervical mucus, and creating a thin, atrophic endometrium not conducive to sustaining the fertilized ovum 11

Choice of Contraceptives Estrogen-progestin oral contraceptives Classified according to estrogen content and formulation Monophasic, biphasic, triphasic, and four-phasic Extended- or continuous-cycle oral contraceptives Decrease or eliminate hormone-free interval 12

Choice of Contraceptives (cont’d.) Progestin-only contraceptives Recommended for patients who do not tolerate estrogen or in whom it is contraindicated Progestin-containing intrauterine device Mirena contains a reservoir of levonorgestrel, a synthetic progestin Releases small amounts of progesterone daily, providing five years of continuous contraception protection 13

Choice of Contraceptives (cont’d.) Postcoital contraception Combined estrogen-progestin contraceptive pills used in case of emergency Not without risk Available option to women who are exposed to an unintentional risk of pregnancy Examples: Next Choice and ulipristal acetate 14

Drugs for Labor and Delivery Oxytocin is a hormone that stimulates the uterus to contract, thus inducing childbirth Also acts on the mammary gland to stimulate the release of milk Synthetic chemicals used to stimulate uterine contractions are called oxytocics Include oxytocin and prostaglandin E1 and E2 Goal of labor induction Facilitate vaginal delivery of a healthy infant 15

Drugs for Labor and Delivery (cont’d.) Prostaglandins are released as a natural part of the cervical ripening process Those causing contraction of the myometrial muscle include dinoprostone or prostaglandin E2 (Prostin E2, Cervidil, Prepidil), and the oral synthetic prostaglandin E1 analog, misoprostol (Cytotec), and the prostaglandin F2-alpha analog carboprost (Hemabate) 16

Drugs for Labor and Delivery (cont’d.) Mifepristone (RU-486) Antiprogesterone drug used to terminate an unwanted pregnancy (in conjunction with misoprostol) Only for use very early in pregnancy Methylergonovine Semisynthetic ergot alkaloid used for prevention and treatment of postpartum and postabortion hemorrhage 17

Drugs for Labor and Delivery (cont’d.) Terbutaline Classified as a bronchodilator drug Also used with careful monitoring in the management of preterm labor Magnesium sulfate For prevention and control of seizures in eclamptic patients Preeclampsia is characterized by new-onset hypertension, edema, and proteinuria during pregnancy 18

Other Gonadotropic Drugs Gonadotropin-releasing hormones (GnRH) Act in the pituitary to suppress ovarian and testicular hormone production and inhibit estrogen and androgen synthesis GnRH analogs that inhibit gonadotropin secretion are used in the management of endometriosis Examples: Lupron and Synarel 19