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