Module 3: Chapter 50 Drugs Affecting Pituitary, thyroid, parathyroid and hypothalamic function Flashcards
what are the functions of the anterior lobe of the pituitary gland?
controls the fn of glucocorticoid hormone levels (ACTH)
body growth and metabolism (GH)
fn of the thyroid gland (TSH)
gonadal function (FSH and LH)
milk production and breast growth (prolactin)
what is the fn of the posterior lobe of the pituitary gland
stores and secretes two effector hormones: oxytocin and vasopressin (ADH)
what are effector hormones
hormones that produce an effect when stimulated
what is the fn of the thyroid gland
control cellular metabolism and promotes normal growth and development
what are the 3 target organs of the parathyroid gland
bone
kidneys
GI tract
what is the major controlling factor for PTH secretion
serum calcium
What are the 6 hormones from the hypothalamus
oxytocin vasopressin (ADH) CRH TRH GHRH SRIF GnRH PRF PIF
what hormones from the hypothalamus affect the posterior pituitary
oxytocin
vasopressin (ADH)
what hormones affect the anterior pituitary
CRH TRH GHRH SRIF GnRH PRF PIF
what does anterior pituitary gland dysfunction include
growth hormone deficiency and excess
what does posterior pituitary gland dysfunction manifest as
diabetes insipidus (DI) syndrome of inappropriate antidiuretic hormone (SIADH)
what does thyroid gland dysfunction manifest as
hyperfunctioning or hypofunctioning gland, malfunctions that may be caused by either a congenital defect or by a problem that occurs later in life
parathyroid gland is a major regulator of ____ _____ and _______
serum calcium and phosphate
parathyroid gland dysfunction can manifest in what two ways
decr. in serum calcium is the dominant regulator of PTH, with a response rate of just a few seconds
decr. in phosphate causes an indirect effect on PTH by combining with calcium and decreasing serum calcium concentrations
what odes GH deficiency lead to
short stature
how was GH deficiency initially treated
GH injections extracted from the pituitary glands of cadavers
how is GH deficiency treated now
synthetic GH (rhGH), produced from recombinant DNA is available but is very expensive
what is the prototype for growth hormones
somatropin
when is somatropin used
as long-term replacement of inadequate endogenous GH secretions
how is somatropin administered
SC and IM
how is somatropin excreted
liver and kidneys
how does somatropin work
stimulates cell growth and cellular mitosis
facilitates cellular uptake of a.a for protein synthesis
promotes use of fatty acids for energy
are their any contraindications and precautions associated with somatropin
contraindicated in growth promotion in children with closed epiphyses
adverse effects associated with somatropin
headache HTN joint and back pain peripheral edema muscle aches rhinitis
what are the drug interactions for somatropin
anabolic steroids androgens estrogens thyroid hormones (these may accelerate epiphyseal maturation)
what pregnancy category is somatropin
category C
How can you maximize therapeutic effects for somatropin
pts who require chronic cycling peritoneal dialysis should receive their doses of somatropin in the morning after the dialysis is completed
what can occur during somatropin therapy
hypothyroidism
insulin resistance
be alert for the development of a limp or complaints of hip or kneww pain, and tell parents to do the same
what is an important part of patient teaching for somatropin
explain taht this drug is replacing an important hormone (GH)
what ongoing assessment and evaluation should be done during somatropin therapy
evalutate thyroid fn at regular intervals because hypothyroidism compromises rGH drug effects
what lab values should a patient taking somatropni have monitored on a routine basis due to adverse effects of the drug therapy?
TSH (somatropin can cause hypothroidisim) Glucose lvl (can cause glucose intolerance)
The posterior pituitary stores two hormones that are produced in the hypothalamus, what are they
vasopressin and oxytocin
what are the synthetic analogues of the hormones that are stored in the posterior pituitary
desmopressin and vasopressin
what is the prototype drug for posterior pituitary hormone regulators
desmopressin
what does desmopressin do
manages central DI and nocturnal enuresis and maintains homeostasis in hemophilia A
how is desmopressin administered
intranasally
orally
parenterally (IV or SC)
where is desmopressin metabolized ?
excreted?
liver
kidneys
what receptors does desmopressin interact with
V1 and V2
what are some adverse effects of desmopressin
abdominal pain transient headache nasal congestion nausea rhinitis facial flushing
what are known drug interactions for desmopressin
carbamazepine
chlorpromazine
nonsteroidal anti-inflammatory drugs
what pregnancy category is desmopressin
category b
what lifestyle diet and habits should be assesed with desmopressin treatment
lifestyle activites and use of recreational drugs
how can you maxmize therapeutic effects for desmopressin
establish baseline values for weight, BP, electrolytes and urine specific gravity
protect ADH solutions from agitation and temperature extremes
how can you mimimize adverse effects for desmopressin
assess for preexisting CV or renal disorders and monitor patients carefully for cardiac reactions from desmopressin
what can alter the therapeutic response to desmopressin
alcohol
what should you instruct patients to monitor for during desmopressin therapy to ensure drug efficacy
monitor urine specific gravity and intake and output as well as to weigh themselves daily
what is desmopressing used to treat
central DI
primary noctunral enuresis
hemophilia A
von willebrand disease type 1
true or false: thyroid hromones influence essentially every organ system in the body
ture
is hyperthyroidism or hypothyroidism commonly mistaken for the normal aging process
hypo
what is the only treatment for hypothyroidism
lifelong replacement of thryoid hormones that are adequate to mee tthe individuals metabolic needs
what is the prototype drug for thyroid drugs
levothyroxine (T4; levothroid, syntrhoid)
what is levothryoxine used for
replacement theory in hypothyroidism
how is levothryoxine administered
orally
what organ metabolizes levothryoxine? how is ti excreted?
liver
bile
what is the onset for levothyroxine
6-8 hours
how does levothryoxine work?
acts as a replacement for natural thyroid hormone
what are the contraindications and precautions associated with levothryoxine
hypersensitivity
thyrotoxicosis
acute MI complicated by hypothyroidism
what are the adverese effects of levothryoxine
HTN tachycardia arrhythmias anxiety headache nervousness GI irritation sweating heat intolerance
are there any drug itneractions with levothyroxine
many drugs
what pregnancy class is levothryoxine
category A
what should be monitored during levothryoxine drug therapy to maximize therapeutic effects
cardiovascular response and serum thyroid function
true or false: young adults without evidence of coronary artery disease can begin a full replacement dose of levothyroxine
true
what is important patient and family education is important during levothryoxine therapy
avoid OTC drugs
what ongoing assessment is necssary with levothyroxine
monitor serum thyroid hormone levels periodically
levothryoxine is a what pregnancy category drug
A
what is hyperthyroidism treated with
thyroid-hormone antagonist drugs
surgery
radioactive iodine
what is the purpose of antithyroid compounds
reduce the amount of functional thyroid tissue
what is the prototype drug for antithyroid compounds
methimazole (MMI)
what is methimazole used for
palliative treatment of hyperthyroidism
how is methimazole administered
oraly
where is methimazole metabolized? excreted?
liver
kidneys
how does methimazole work
inhibits the synthesis of thyroid hormones
what are the adverse effects associated with methimazole
hives itching rash fever arthralgia joint swelling vertigo drowsiness N/V altered taste sensation
what drugs are known to have interactions with methimazole
beta-blocking agents
theophylline
warfarin
what pregnancy category does methimazole lead to
category D
what are two ways that adverse effects can be minimized with methimazole
arrange for periodic blood tests to monitor for hematologic and thyroid fn
monitor pts bone marrow fn
what important teaching is necessary with methimazole
if the drug is taken in divided doses the patient should take them every 8 hours aroundt he clock
what ongoing assessment and evaluation is necessary for methimazole
monitor serum thyroid homrone levles to evaulate effectiveness of MMI adn to asess the need for replacement thyroid hormone since the thyroid gland is supressed
methimazole belongs to what pregnancy category?
D
do antihypercalcemic drugs directly affect the parathyroid gland or PTH
no
how do antihyperglycemic drugs work
inhibit bone resorption of calcium
what disease are antihypercalcemic drugs used for treatment in
paget diseae
individuals with sypmtomatic disease expereince bone pain and deformity, fractures, spinal cord compression or cranial and spinal cord entrapment are often perscribed whtat type of drug
antihypercalcemic
what is the prototype drug for the class antihypercalcemic, calcium-regulator drugs
calcitonin
what is another name for symptomatic disease
Paget disease
what are the symptoms of paget disease
bone pain bone deformity fractures spinal cord compression cranial and spinal cord entrapment
how is calcitonin commonly administered
SC, IM or intranasal
how is calcitonin metabolized and excreted
kidneys for both!
What is a contraindication and precaution for calcitonin
salmon allergies
what are the adverse effects associated with calcitonin
GI distubrnaces skin rash flushing of the face and hands nasal irritation rhinitis (if using the nasal spray)
what drug interactions are known regarding calcitonin
calcium supplements
antacids
vitamin D
theophylline
what pregnany category does calcitonin belong to
C
for paget disease what route is necessary to give calcitonin
injection
what are the most common adverse effects with SC or IM adminsitration of calcitonin
nausea
what are the most common adverese effects of nasal calcitonin
rhinitis
nasal crusts
dryness
what important patient and family education is important in calcitonin therapy
to report twitching, muscle pain, severe diarrhea or dark urine
why must serum calcium level be assessed and evaluated during treatment
because calcitonin can cause the serum clacium level to drop resulting in tetany and cardiac arrhythmia
is there an increase in the therapeutic effect of calcitonin when it is administered with vitamin D
no,
what are the 4 things that can put clients at risk for hypercalcemia if they are taking calcitonin
salmon
calcium supplements
antacids
vitamin d
what do vitamin D compounds do
regulate absorption of calcium and phosphate
is vitamin D a natural hormone
no
is considered a hormone but not a natural hormone
what do vitamin D metabolites control
intestinal absorption of dietary caclicum
reabsorption of Ca by the kidney
bobilization of Ca from the skeleton in conjunction with PTH
Vitamin D is also involved in what elements metabolism
magnesium!
vitamin D works toether with what two things to regulate calcium hometostasis
PTH and calcitonin
what is the prototype antihypocalcemic drug?
calcitrol
1,250dihydroxyvitamin D3, Rocaltrol [capsules, solution], Calcijex [parenteral]
what is calcitrol used for
management of hypocalcemia
how is calcitrol administered
orally or IV
where is calcitrol metabolized? where is it excreted?
liver
urine and feces
how does calcitrol work? i.e what are it’s pharmacodynamics
fat-soluble vitamin derived from natural sources (fish liver oils) or from conversion of provitamins
what are the contraindications and precautions regarding calcitrol treatment
give carefully to patients at risk for hypercalcemia and hypercalciuria
what are the adverse effects for calcitrol
weakness headache N/V dry mouth constipation bone pain
are there any known drug interactions for calcitriol
thiazie diuretics
what pregnancy category does calcitriol belong to?
C
why are IV doses of calcitriol given following dialysis
to increase calcium levels
can calcitrol capsules be broken, crushed or chewed?
capsules should always be swalled whole
if high therapeutic doses of calcitriol are used, what is important to monitor
frequent serum and urinary calcium, phosphate and BUN determinations are necessary
what should chronic dialysis patients avoid taking when on calcitriol
magnesium containing antacids
True or False: calcitriol dosing guidelines are established for all age groups
false:
dosing guidelines for patients with hypoparathyroidism who are <1y.o, or pts wih pseudohypoppartahtyroidism who are younger than 6 years have not been established
