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P A R T 7
Drugs acting on the reproductive system
BOX 40.1
Drug therapy across the lifespan
Drugs affecting the female reproductive system
CHILDREN
The oestrogens and progestins have undergone little
testing in children. Because of their effects on closure of
the epiphyses, they should be used only with great caution
in growing children.
If oral contraceptives are prescribed for teenage girls,
the smallest dose possible should be used and the child
should be monitored carefully for metabolic and other
effects.
ADULTS
Women who are receiving any of these drugs should
receive an annual medical examination, including breast
examination and Pap smear, to monitor for adverse
effects and underlying medical conditions.The potential
for adverse effects should be discussed and comfort
measures provided. Women taking oestrogen should be
advised not to smoke because of the increased risk of
thrombotic events.
If any of these drugs is used in males for the treatment
of specific cancers, the person should be advised about
the possibility of oestrogenic effects and appropriate
support should be offered.
PREGNANCY AND BREASTFEEDING
When combinations of these hormones are used as
part of fertility programs, women need a great deal of
psychological support and comfort measures to cope with
the many adverse effects associated with these drugs.
The risk of multiple births should be explained, as should
the need for frequent monitoring.
When prostaglandins are used, people need a great
deal of psychological support. Written lists of signs and
symptoms to report and what to expect are more effective
than just verbal lists in this time of potential stress.
These agents are not for use during pregnancy or
breastfeeding because of the potential for adverse effects
on the fetus or neonate.
OLDER ADULTS
Hormone replacement therapy (HRT) is no longer
commonly used by postmenopausal women. Reports of
benefits and risks are frequent and conflicting, and women
need support and reliable information to make informed
decisions about the use of these drugs.
If women are also using alternative therapies, their
effects on the HRT and other possible prescription drugs
need to be carefully evaluated.
TABLE 40.1
DRUGS IN FOCUS Sex hormones and oestrogen receptor modulators
Drug name
Dosage/route
Usual indications
Sex hormones
Oestrogens
oestradiol (Estrofem,
Estradot)
Transdermal patch: 2-8 mg/day topically
Tablet: 1–2 mg/day PO
Hormone replacement therapy; short-term
management of oestrogen deficiency
due to menopause
oestrogens conjugated
(Premarin)
0.3–1.25 mg/day PO
Management of signs and symptoms of
menopause, prostate cancer, inoperable
breast cancer; treatment of female
hypogonadism, postpartum breast
engorgement; to retard the progress of
osteoporosis
Progestogens
desogestrel (Marvelon)
desogestrel 0.15 mg with 30 mcg
ethinyloestradiol, 1 tab PO daily
Available only in combination form, used as
oral contraceptive
drospirenone (Yasmin,
YAZ)
Yasmin: 3 mg with 30 mcg ethinyloestradiol
YAZ: 3 mg with 0.02 mg oestradiol
Used in combination contraceptives;
treatment of acne and premenstrual
dysphoric disorder (PMDD); relief of
signs and symptoms of menopause
etonogestrel (Implanon,
NuvaRing)
Implanon: 68 mg implanted subdermally for up
to 3 years, may be replaced at that time
NuvaRing: 0.12 mg with 0.015 mg
ethinyloestradiol as a vaginal ring
Contraceptive for women; being
investigated as a male contraceptive
agent
levonorgestrel (Mirena,
Levonelle)
Mirena: 52 mg inserted intrauterine for up to
5 years
Levonelle: 1.5 mg PO taken within 72 hours of
sexual intercourse
Intrauterine contraceptives; also used as
“morning after” pill; component in many
combination contraceptives
medroxyprogesterone
(Provera)
5–10 mg/day PO for 5–10 days for
amenorrhoea; 200–500 mg/day PO for
cancer therapy
Treatment of amenorrhoea (orally);
palliation of certain cancers (injection)
