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INDICATIONS AND
USAGE CLOMID is
indicated for the treatment of ovulatory dysfunction
in women desiring pregnancy. Impediments to achieving
pregnancy must be excluded or adequately treated
before beginning CLOMID therapy. Those patients
most likely to achieve success with clomiphene therapy
include patients with polycystic ovary syndrome
(see WARNINGS : Ovarian Hyperstimulation Syndrome
), amenorrhea-galactorrhea syndrome, psychogenic
amenorrhea, post-oral-contraceptive amenorrhea,
and certain cases of secondary amenorrhea of undetermined
etiology. Properly timed coitus in relationship
to ovulation is important. A basal body temperature
graph or other appropriate tests may help the patient
and her physician determine if ovulation occurred.
Once ovulation has been established, each course
of CLOMID should be started on or about the 5th
day of the cycle. Long-term cyclic therapy is not
recommended beyond a total of about six cycles (including
three ovulatory cycles). See DOSAGE AND ADMINISTRATION
and PRECAUTIONS .) CLOMID is indicated only in patients
with demonstrated ovulatory dysfunction who meet
the conditions described below (see CONTRAINDICATIONS
): Patients who are not pregnant.
Patients without ovarian cysts. CLOMID should not
be used in patients with ovarian enlargement except
those with polycystic ovary syndrome. Pelvic examination
is necessary prior to the first and each subsequent
course of CLOMID treatment. Patients without abnormal
vaginal bleeding. If abnormal vaginal bleeding is
present, the patient should be carefully evaluated
to ensure that neoplastic lesions are not present.
Patients with normal liver function. In addition,
patients selected for CLOMID therapy should be evaluated
in regard to the following: Estrogen Levels. Patients
should have adequate levels of endogenous estrogen
(as estimated from vaginal smears, endometrial biopsy,
assay of urinary estrogen, or from bleeding in response
to progesterone). Reduced estrogen levels, while
less favorable, do not preclude successful therapy.
Primary Pituitary or Ovarian Failure. CLOMID therapy
cannot be expected to substitute for specific treatment
of other causes of ovulatory failure. Endometriosis
and Endometrial Carcinoma. The incidence of endometriosis
and endometrial carcinoma increases with age as
does the incidence of ovulatory disorders. Endometrial
biopsy should always be performed prior to CLOMID
therapy in this population. Other Impediments to
Pregnancy. Impediments to pregnancy can include
thyroid disorders, adrenal disorders, hyperprolactinemia,
and male factor infertility. Uterine Fibroids. Caution
should be exercised when using CLOMID in patients
with uterine fibroids due to the potential for further
enlargement of the fibroids. There are no adequate
or well-controlled studies that demonstrate the
effectiveness of CLOMID in the treatment of male
infertility. In addition, testicular tumors and
gynecomastia have been reported in males using clomiphene.
The cause and effect relationship between reports
of testicular tumors and the administration of CLOMID
is not known. Although the medical literature suggests
various methods, there is no universally accepted
standard regimen for combined therapy (ie, CLOMID
in conjunction with other ovulation-inducing drugs).
Similarly, there is no standard CLOMID regimen for
ovulation induction in in vitro fertilization programs
to produce ova for fertilization and reintroduction.
Therefore, CLOMID is not recommended for these uses.
CLINICAL PHARMACOLOGY
Action CLOMID is a drug of considerable pharmacologic
potency. With careful selection and proper management
of the patient, CLOMID has been demonstrated to
be a useful therapy for the anovulatory patient
desiring pregnancy. Clomiphene citrate is capable
of interacting with estrogen-receptor-containing
tissues, including the hypothalamus, pituitary,
ovary, endometrium, vagina, and cervix. It may compete
with estrogen for estrogen-receptor-binding sites
and may delay replenishment of intracellular estrogen
receptors. Clomiphene citrate initiates a series
of endocrine events culminating in a preovulatory
gonadotropin surge and subsequent follicular rupture.
The first endocrine event in response to a course
of clomiphene therapy is an increase in the release
of pituitary gonadotropins. This initiates steroidogenesis
and folliculogenesis, resulting in growth of the
ovarian follicle and an increase in the circulating
level of estradiol. Following ovulation, plasma
progesterone and estradiol rise and fall as they
would in a normal ovulatory cycle. Available data
suggest that both the estrogenic and antiestrogenic
properties of clomiphene may participate in the
initiation of ovulation. The two clomiphene isomers
have been found to have mixed estrogenic and antiestrogenic
effects, which may vary from one species to another.
Some data suggest that zuclomiphene has greater
estrogenic activity than enclomiphene. Clomiphene
citrate has no apparent progestational, androgenic,
or antiandrogenic effects and does not appear to
interfere with pituitary-adrenal or pituitary-thyroid
function. Although there is no evidence of a "carryover
effect" of CLOMID, spontaneous ovulatory menses
have been noted in some patients after CLOMID therapy.
Pharmacokinetics Based on early studies with 14
C-labeled clomiphene citrate, the drug was shown
to be readily absorbed orally in humans and excreted
principally in the feces. Cumulative urinary and
fecal excretion of the 14 C averaged about 50% of
the oral dose and 37% of an intravenous dose after
5 days. Mean urinary excretion was approximately
8% with fecal excretion of about 42%. Some 14 C
label was still present in the feces 6 weeks after
administration. Subsequent single-dose studies in
normal volunteers showed that zuclomiphene (cis)
has a longer half-life than enclomiphene (trans).
Detectable levels of zuclomiphene persisted for
longer than a month in these subjects. This may
be suggestive of stereo-specific enterohepatic recycling
or sequestering of the zuclomiphene. Thus, it is
possible that some active drug may remain in the
body during early pregnancy in women who conceive
in the menstrual cycle during CLOMID therapy.
CLOMID CLINICAL STUDIES
During clinical investigations, 7578 patients
received CLOMID, some of whom had impediments to
ovulation other than ovulatory dysfunction (see
INDICATIONS AND USAGE ). In those clinical trials,
successful therapy characterized by pregnancy occurred
in approximately 30% of these patients. There were
a total of 2635 pregnancies reported during the
clinical trial period. Of those pregnancies, information
on outcome was only available for 2369 of the cases.
Table 1 summarizes the outcome of these cases. Of
the reported pregnancies, the incidence of multiple
pregnancies was 7.98%: 6.9% twin, 0.5% triplet,
0.3% quadruplet, and 0.1% quintuplet. Of the 165
twin pregnancies for which sufficient information
was available, the ratio of monozygotic to dizygotic
twins was about 1:5. Table 1 reports the survival
rate of the live multiple births. A sextuplet birth
was reported after completion of original clinical
studies; none of the sextuplets survived (each weighed
less than 400 g), although each appeared grossly
normal. Table 1. Outcome of Reported Pregnancies
in Clinical Trials (n = 2369) Outcome Total Number
of Pregnancies Survival Rate Pregnancy Wastage Spontaneous
Abortions Stillbirths 483 * 24 Live Births Single
Births Multiple Births 1697 165 98.16% ** 83.26%
** * Includes 28 ectopic pregnancies, 4 hydatiform
moles, and 1 fetus papyraceous. ** Indicates percentage
of surviving infants from these pregnancies. The
overall survival of infants from multiple pregnancies
including spontaneous abortions, stillbirths, and
neonatal deaths is 73%.
CLOMID CONTRAINDICATIONS
Hypersensitivity CLOMID is contraindicated in patients
with a known hypersensitivity or allergy to clomiphene
citrate or to any of its ingredients. Pregnancy
CLOMID should not be administered during pregnancy.
CLOMID may cause fetal harm in animals (see Animal
Fetotoxicity). Although no causative evidence of
a deleterious effect of CLOMID therapy on the human
fetus has been established, there have been reports
of birth anomalies which, during clinical studies,
occurred at an incidence within the range reported
for the general population (see Fetal/Neonatal Anomalies
and Mortality; ADVERSE REACTIONS ). To avoid inadvertent
CLOMID administration during early pregnancy, appropriate
tests should be utilized during each treatment cycle
to determine whether ovulation occurs. The patient
should be evaluated carefully to exclude pregnancy,
ovarian enlargement, or ovarian cyst formation between
each treatment cycle. The next course of CLOMID
therapy should be delayed until these conditions
have been excluded. Fetal/Neonatal Anomalies and
Mortality. The following fetal abnormalities have
been reported subsequent to pregnancies following
ovulation induction therapy with CLOMID during clinical
trials. Each of the following fetal abnormalities
were reported at a rate of <1% (experiences are
listed in order of decreasing frequency): Congenital
heart lesions, Down syndrome, club foot, congenital
gut lesions, hypospadias, microcephaly, harelip
and cleft palate, congenital hip, hemangioma, undescended
testicles, polydactyly, conjoined twins and teratomatous
malformation, patent ductus arteriosus, amaurosis,
arteriovenous fistula, inguinal hernia, umbilical
hernia, syndactyly, pectus excavatum, myopathy,
dermoid cyst of scalp, omphalocele, spina bifida
occulta, ichthyosis, and persistent lingual frenulum.
Neonatal death and fetal death/stillbirth in infants
with birth defects have also been reported at a
rate of <1%. The overall incidence of reported birth
anomalies from pregnancies associated with maternal
CLOMID ingestion during clinical studies was within
the range of that reported for the general population.
In addition, reports of birth anomalies have been
received during postmarketing surveillance of CLOMID
(see ADVERSE REACTIONS ). Animal Fetotoxicity. Oral
administration of clomiphene citrate to pregnant
rats during organogenesis at doses of 1 to 2 mg/kg/day
resulted in hydramnion and weak, edematous fetuses
with wavy ribs and other temporary bone changes.
Doses of 8 mg/kg/day or more also caused increased
resorptions and dead fetuses, dystocia, and delayed
parturition, and 40 mg/kg/day resulted in increased
maternal mortality. Single doses of 50 mg/kg caused
fetal cataracts, while 200 mg/kg caused cleft palate.
Following injection of clomiphene citrate 2 mg/kg
to mice and rats during pregnancy, the offspring
exhibited metaplastic changes of the reproduction
tract. Newborn mice and rats injected during the
first few days of life also developed metaplastic
changes in uterine and vaginal mucosa, as well as
premature vaginal opening and anovulatory ovaries.
These findings are similar to the abnormal reproductive
behavior and sterility described with other estrogens
and antiestrogens. In rabbits, some temporary bone
alterations were seen in fetuses from dams given
oral doses of 20 or 40 mg/kg/day during pregnancy,
but not following 8 mg/kg/day. No permanent malformations
were observed in those studies. Also, rhesus monkeys
given oral doses of 1.5 to 4.5 mg/kg/day for various
periods during pregnancy did not have any abnormal
offspring. Liver Disease. CLOMID therapy is contraindicated
in patients with liver disease or a history of liver
dysfunction (see also INDICATIONS AND USAGE and
ADVERSE REACTIONS ). Abnormal Uterine Bleeding.
CLOMID is contraindicated in patients with abnormal
uterine bleeding of undetermined origin (see INDICATIONS
AND USAGE ). Ovarian Cysts. CLOMID is contraindicated
in patients with ovarian cysts or enlargement not
due to polycystic ovarian syndrome (see INDICATIONS
AND USAGE and WARNINGS ). Other. CLOMID is contraindicated
in patients with uncontrolled thyroid or adrenal
dysfunction or in the presence of an organic intracranial
lesion such as pituitary tumor (see INDICATIONS
AND USAGE ).
CLOMID WARNINGS Visual
Symptoms Patients should be advised that blurring
or other visual symptoms such as spots or flashes
(scintillating scotomata) may occasionally occur
during therapy with CLOMID. These visual symptoms
increase in incidence with increasing total dose
or therapy duration and generally disappear within
a few days or weeks after CLOMID is discontinued.
Patients should be warned that these visual symptoms
may render such activities as driving a car or operating
machinery more hazardous than usual, particularly
under conditions of variable lighting. These visual
symptoms appear to be due to intensification and
prolongation of afterimages. Symptoms often first
appear or are accentuated with exposure to a brightly
lit environment. While measured visual acuity usually
has not been affected, a study patient taking 200
mg CLOMID daily developed visual blurring on the
7th day of treatment, which progressed to severe
diminution of visual acuity by the 10th day. No
other abnormaltiy was found, and the visual acuity
returned to normal on the 3rd day after treatment
was stopped. Ophthalmologically definable scotomata
and retinal cell function (electroretinographic)
changes have also been reported. A patient treated
during clinical studies developed phosphenes and
scotomata during prolonged CLOMID administration,
which disappeared by the 32nd day after stopping
therapy. Postmarketing surveillance of adverse events
has also revealed other visual signs and symptoms
during CLOMID therapy (see ADVERSE REACTIONS ).
While the etiology of these visual symptoms is not
yet understood, patients with any visual symptoms
should discontinue treatment and have a complete
ophthalmological evaluation carried out promptly.
Ovarian Hyperstimulation Syndrome The ovarian hyperstimulation
syndrome (OHSS) has been reported to occur in patients
receiving clomiphene citrate therapy for ovulation
induction. In some cases, OHSS occurred following
cyclic use of clomiphene citrate therapy or when
clomiphene citrate was used in combination with
gonadotropins. Transient liver function test abnormalities
suggestive of hepatic dysfunction, which may be
accompanied by morphologic changes on liver biopsy,
have been reported in association with ovarian hyperstimulation
syndrome (OHSS). OHSS is a medical event distinct
from uncomplicated ovarian enlargement. The clinical
signs of this syndrome in severe cases can include
gross ovarian enlargement, gastrointestinal symptoms,
ascites, dyspnea, oliguria, and pleural effusion.
In addition, the following symptoms have been reported
in association with this syndrome: pericardial effusion,
anasarca, hydrothorax, acute abdomen, hypotension,
renal failure, pulmonary edema, intraperitoneal
and ovarian hemorrhage, deep venous thrombosis,
torsion of the ovary, and acute respiratory distress.
The early warning signs of OHSS are abdominal pain
and distention, nausea, vomiting, diarrhea, and
weight gain. Elevated urinary steroid levels, varying
degrees of electrolyte imbalance, hypovolemia, hemoconcentration,
and hypoproteinemia may occur. Death due to hypovolemic
shock, hemoconcentration, or thromboembolism has
occurred. Due to fragility of enlarged ovaries in
severe cases, abdominal and pelvic examination should
be performed very cautiously. If conception results,
rapid progression to the severe form of the syndrome
may occur. To minimize the hazard associated with
occasional abnormal ovarian enlargement associated
with CLOMID therapy, the lowest dose consistent
with expected clinical results should be used. Maximal
enlargement of the ovary, whether physiologic or
abnormal, may not occur until several days after
discontinuation of the recommended dose of CLOMID.
Some patients with polycystic ovary syndrome who
are unusually sensitive to gonadotropin may have
an exaggerated response to usual doses of CLOMID.
Therefore, patients with polycystic ovary syndrome
should be started on the lowest recommended dose
and shortest treatment duration for the first course
of therapy (see DOSAGE AND ADMINISTRATION ). If
enlargement of the ovary occurs, additional CLOMID
therapy should not be given until the ovaries have
returned to pretreatment size, and the dosage or
duration of the next course should be reduced. Ovarian
enlargement and cyst formation associated with CLOMID
therapy usually regress spontaneously within a few
days or weeks after discontinuing treatment. The
potential benefit of subsequent CLOMID therapy in
these cases should exceed the risk. Unless surgical
indication for laparotomy exists, such cystic enlargement
should always be managed conservatively. A causal
relationship between ovarian hyperstimulation and
ovarian cancer has not been determined. However,
because a correlation between ovarian cancer and
nulliparity, infertility, and age has been suggested,
if ovarian cysts do not regress spontaneously, a
thorough evaluation should be performed to rule
out the presence of ovarian neoplasia. PRECAUTIONS
General Careful attention should be given to the
selection of candidates for CLOMID therapy. Pelvic
examination is necessary prior to CLOMID treatment
and before each subsequent course (see CONTRAINDICATIONS
and WARNINGS ).
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