drugs affecting the endocrine system Flashcards
describe the neuroendocrine system
- endcrine and nervous system work together
- maintain homeostasis
- respond to environment
- endocrine system has glands and hormones
endocrine system communicates within the body to…
- regulate growth and development
- regulate energy use
- balance electrolytes
- respond to internal and external stressors
what do glands do
- produce hormones
- secrete directly into the bloodstream
describe hormones
- produced in small amounts (on an as needed basis)
- secreted directly into the bloodstream
- attach to receptor sites
- increase or decrease cellular function
- broken down imediately
endocrine system works in two ways, what are they?
1) react with specific receptor sites on the cell (ex. insulin)
2) enter cell and react with a receptor site inside the cell (ex. estrogen)
overproduction or underproduction affects body activities
the thyroid gland produces three hormones, what are they?
- T3
- T4
- calcitonin
describe the structure and function of the thyroid gland
- vascular (lots of blood)
- circular follicles (store hormones)
- parafollicular cells (produce calcitonin) - effects calcium levels and effects PTH
what do thyroid hormones do?
- main regulator of metabolism
- affect heat production
- affect body temp
- oxygen consuption/CO
- blood volume
- metabolism of CHO, fats, proteins
- growth and development
describe the control of the thyroid gland
- TH production and release regulated by TSH
- negative feedback loop (only made when its needed, not stored)
name two types of thyroid dysfunction
- hypothyroidism
- hyperthyroidism
why might there be a lack of thyroid hormones?
- absence of thyroid gland
- lack of iodine (needed to make T3 and T4)
- lack of functioning thyroid tissue
- lack of TSH or TRH
what are some conditions associated with hypothyroidism
- myxedema (severe hypothyroidism)
- myxedema coma (happens if myxedema is not treated)
what are some signs and symptoms of hypothyroidism
- hair loss
- dry skin
- lethargy
- constipation
- cold intolerance
- bradycardia
- arrhythmias
- weight gain
slows everything down
why might there be excessive amounts of thyroid hormone
- grave’s disease (autoimmune disorder that stimulates TSH to release thyroid hormons)
- overstimulation from TSH
- thyroid storm (really high thyroid level, can be fatal)
- enlarged thyroid (more thyroid = more hormone)
whata are some signs and symptoms of hyperthyroidism
- tremors
- fine, thin hair
- bulging eyes
- tachycardia
- weight loss
- HTN
everything is turned up
describe drug therapy for hyperthyroidism
goal: reduce thyroid hormone
- antithyroid drugs
- surgical removal
describe drug therapy for hypothyroidism
goal: thyroid hormone replacement
- monitor TSH (this is the most reliable marker)
- also monitor T3 and T4
give an example of antithyroid drugs
propylthiouracil (PTU)
describe the action of PTU
inhibits production of thyroid hormone, takes 1-2wks
what is PTU used for
hyperthyroidism
what are some adverse effects of PTU
- hypothyroidism
- bone marrow suppression
- black box warning for liver failure
give an example of an iodine solution
lugols solution
what is lugols solution used for
given before OR to reduce size and vascularity of thyroid gland
whats important to remember about lugols solution
- not safe with pregnancy
- may discolor teeth, drink with straw
what are some nursing considerations for anti-thyroid drugs
- increases effect of anticoagulants (slower metabolism)
- may take 1-2wks to start working
- monitor liver function
- monitor metabolsim of other drugs as metabolism slows
describe patient education for anti-thyroid drugs
- take evenly around the clock and always with or always without food to ensure the same effectiveness daily
- may take 1-2wks to start working
- alert MD to s/sx of liver failure
- may need blood draws to monitor therpeutic level
- will need lifelong thyroid hormone replacement
give an example of a thyroid drug
levothyroxine
describe the action of levothyroxine
sythetic T4, increases metabolic rate
what is levothyroxine used for
- hypothyroidism
- thyroid cancer
what are some adverse effects of levothyroxine
hyperthyrodism
- tachycardia, CP, MI, nervousness, insomnia, weight loss
what are some contraindications of levothyroxine
acute MI
what are some nursing considerations for levothyroxine
- goal TSH 0.5-4.2 microunits/L
- many drug-drug interactions (increases effects of anticoagulants)
- monitor metabolism of other drugs as metabolism increases
- monitor for stress on heart
describe patient education for levothyroxine
- take in morning on empty stomach
- frequent lab draws needed early
- periodic labs drawn later in therapy
- lifelong replacement
what should the nurse assess prior to administration of levothyroxine?
1) blood glucose
2) HR
3) lung sounds
4) urine output
2) HR
levothyroxine is going to stimulate metabolism, increasing cardiac workload and stress on the heart. the heart may beat harder and faster to meet those demands, assess for tachycardia before giving the med
levothyroxine is ordered at 0900 in the hospital, the nurse knows that breakfast comes between 0800-0830, what should the nurse do?
1) give the med with breakfast
2) message pharmacy to reschedule med for 2200
3) give med early
4) hold med
3) give med early
levothyroxine needs to be taken on an empty stomach. the nurse needs to make this med a priority before the meal
