Hyperthyroidism Flashcards
What is plummers disease? What is it caused by and whats the difference with Graves disease?
Not cause by AB, but tumour of thryroid gland
NO EXOTHALA:OS and no myxodeama
Large, non smooth thyroxin gland, but still causes hyperthrydoism
With radioactive iodinem shows ‘hot nodule’ instead of whole gland
What are the effects of thyroxin on the SNS?
Sensitises Beta adrenoreceptor to ambient adrenaline/noradrenaline-over sensitive SNS
Tachycardia, palpitations, temors, lid lag (eye lid higher than normal with eye lookin down)
What are the most common symtoms of hyperthyroidism?
Perspiration, Tachy, palpitaion, termors, SOB, Loss of weigh, increase of apetite, diarrhea (or just often)
(exothalamos and myxodema in Graves, smooth Goiter)
Heat intolerance, lid lag
What is a thyroid storm? What are the features
Emergency-50% mortality -extreme amounts of thyroxin
Features: Hyperpyrexia (41C), accelerated tachy, cardiac failure, delirium, hepatocellular dysf
Any of these with hyperthyroidism needs emergency care
What are the treatment options for thyroxin storms>
Surgery, Radio-iodine, drugs
What are the drugs used to treat hyperthyroidism
thinamides (anto thryoid drugs-remember PTU and CBZ), potassium iodide, radio iodinem B blockers
1st three reduce thryxoine production, B blocker only help manage
What are thionamides?
tablet drugs
can be used as:
daily given drugs to treat hyperthyroidism (graves, Toxic thyroid nodule/plummers)
Treatment prior to surgery (reduce risks)
Reduction of symptoms prior to radioactive iodine to act
Usually stop after 18 months (and the review)
How do Thionamides function? How fast does it act?
Blocks Thyroperoxidase and peroxidase transminase (same one)-which create the iodination of the TG, and the re-uptake of the hormonde from the coilloid
act in a few hours-effective, but bioeffects only show after weeks-colloid has a store ready before
(why might use propanolol until)
Also migh supress AB production in graves, and PTU reduces T4->T3 in tissue
What are the unwanted side effects of Thionamides?
Quite safe overall
Agranulocytosis-loss of neutrophils, but RARE-need to be an emergency if happens
Rashes are common but okay, and can just switch drugs
Can Carbimazole cross the placenta?
Carbimazole is pro-drug-methimazole is the active
both can pass placent (can be concern),
PTU can also pass
Both uptaken and excreted by liver
What are the roles of B blockers in Thyroitoxicosis?
Several weeks for ATDs to have a clinical effect
So B blockers reduce the symtopms-but use non-selective one as you want global action (propanolol)
What is protassium Iodine? Why is it used? side effects? How is it goven>
KI- can be used for hyperthyroid patients and for severe thryrotoxic crisis Kinda used for emerency, or surgery Can get allrergic effects orally
How does potassium iodine suppress thyroxine? How fast does it act?
Inhibits the iodination of thryroglobulin, inhbits H2O2 prod and thryoperoxidase
Acts via “Wolff chakoff”-which is presumed autoregulation unique to Thyroid gland (if high I, works less)
Reduce symtoms in 1/2 days and size of gland (good for surgery)
What is radioiodine for treatment for hyperthyroidism?
Treats hyperthyroidism (graves, etc), thyroid cancer Importantly, gives massive DEFINITIVE effects on the thyroid (switch it off for good and give thyroxin drug)-accumulate in Colloid and emits B particules killing the follicular cells good before pregancy-not affect child, gets rid of issue
How is radioiodine given as a treatment?
Discontinue Antithyroid gland before
Single oral dose (much higher dose for cancer)-radioactive half life 8 days-no radioaction after 2 months
Avoid seeing children for a while after
