C H A P T E R 3 5
Hypothalamic and pituitary agents
523
Not all of these hormones are available for pharmaco
logical use (see Table 34.1 in Chapter 34).
Available hypothalamic releasing hormones include
corticotropin-releasing hormone (CRH) (generic), and
goserelin (
Zoladex
) (synthetic GnRH). Available antag
onists that block the effects of hypothalamic releasing
hormones include cetrorelix (
Cetrotide
) (blocks GnRH),
ganirelix (
Orgalutran
) (blocks GnRH), leuprorelin
(
Eligard
,
Lucrin
) (blocks GnRH effects) and nafare
lin (
Synarel
) (blocks GnRH) (not available in New
Zealand). See Table 35.1 for a complete list of these
drugs.
Therapeutic actions and indications
The hypothalamic hormones are found in such minute
quantities that the actual chemical structures of all of
BOX 35.1
Drug therapy across the lifespan
Hypothalamic and pituitary agents
CHILDREN
Children who receive any of the hypothalamic or pituitary
agents need to be monitored closely for adverse effects
associated with changes in overall endocrine function,
particularly growth, development and metabolism.
Periodic radiograph of the long bones, as well as
monitoring of blood sugar levels and electrolytes,
should be a standard part of the treatment plan. Children
receiving growth hormone pose many challenges (see
Box 35.2). Children who are using desmopressin for
diabetes insipidus need to have the administration
technique monitored and should have an adult responsible
for the overall treatment protocol.
ADULTS
Adults also need frequent monitoring of electrolytes and
blood sugar levels when receiving any of these agents.
Adults using nasal forms of drugs to control diabetes
insipidus should review the proper administration of
the drug with the primary care provider periodically;
inappropriate administration can lead to complications
and lack of therapeutic effect. Adults receiving regular
injections of these drugs should learn the proper storage,
preparation and administration of the drug, including
rotation of injection sites.
PREGNANCY AND BREASTFEEDING
These drugs should not be used during pregnancy or
breastfeeding unless the benefit to the mother clearly
outweighs any risk to the fetus or neonate because of the
potential for severe adverse effects associated with the use
of these drugs.
OLDER ADULTS
Older adults may be more susceptible to the imbalances
associated with alterations in the endocrine system.They
should be evaluated periodically during treatment for
hydration and nutrition, as well as for electrolyte balance.
Proper administration technique should be reviewed and
nasal mucous membranes should be evaluated regularly
because older people are more apt to develop dehydrated
membranes and possibly ulcerations, leading to improper
dosing of drugs delivered nasally.
TABLE 35.1
DRUGS IN FOCUS Drugs affecting hypothalamic hormones
Drug name
Dosage/route
Usual indications
Agonists
corticotrophin-releasing
hormone (CRH) (generic)
10–25 units in 500 mL 5% dextrose in water,
infused over 8 hours
Diagnosis of Cushing’s disease; being
studied for treatment of peritumoral brain
oedema
goserelin (Zoladex)
Implant inserted SC into anterior abdominal
wall every three months
Used as an antineoplastic agent for
treatment of specific hormone-stimulated
cancers
Antagonists
cetrorelix (Cetrotide)
250 mcg/d SC lower abdominal wall,
commencing day five to six followed by 3 mg
on day seven of ovarian stimulation
Prevention of ovulation in women
undergoing assisted reproductive
techniques
ganirelix (Orgalutran)
250 mcg SC on day two or three of the
menstrual cycle
Inhibition of premature luteinising hormone
surge in women undergoing controlled
ovarian stimulation as part of a fertility
program
leuprorelin (Eligard,
Lucrin)
Prostate cancer: 1 mg/day SC or various depot
preparations: 3.75 mg IM endometriosis—
once a month
Used as antineoplastic agent for treatment
of specific cancers; treatment of
endometriosis
nafarelin (Synarel)
400 mcg/day divided as one spray in left nostril
a.m. or p.m.; one spray in right nostril a.m. or p.m.
Treatment of endometriosis
