thyroid Flashcards
triiodothyronine
T3
thyroxine
T4
hypothyroidism is
deficiency and consequently an elevation in TSH
key drugs that cause hypothyroidism
I TALC
Interferons (can also cause hyperthyroidism)
Tyrosine kinase inhibitors
Amiodarone (can also cause hyperthyroidism)
Lithium
Carbamazepine
condition:
hashimoto’s disease (autoimmune)
myxedema coma
fatal complication when hypothyroidism is left untreated
tx. IV levothyroxine
symptoms of hypothyroidism
cold intolerance/sensitivity
dry skin
fatigue
muscle cramps
weight gain
constipation
weakness
etc.
low free T4
high TSH
this is
diagnosis of hypothyroidism
normal T4= 0.9-2.3
normal TSH: 0.3-3
monitor 4-6 weeks
levothyroxine
is (T4)
synthroid, Levoxyl, unithyroid
60 min before breakfast or a bedtime (3hours after last meal)
IV:PO 0.75:1 (use immediately upon reconstitution)
contra: uncorrected adrenal insufficiency
potentially toxic for obese or overweight pt boxed warning
thyroid, desiccated USP
is T3 and T4
Armour Thyroid, NP thyroid
“natural thyroid”- natural porcine-derived- less predictable potency and stability
contra: uncorrected adrenal insufficiency
potentially toxic for obese or overweight pt boxed warning
liothyronine
is T3
cytomel
shorter t1/2 causes fluctuations in T3 levels
levothyroxine tablet colors
Orangutans Will Vomit On You Right Before They Become Large Proud Giants
25mcg- orange
50mcg- white (no dye)
75mcg- violet
88mcg- olive
100mcg- yellow
112mcg- rose
125mcg- brown
137mcg- turquoise
150mcg- blue
175mcg- lilac
200mcg- pink
300mcg- green
drugs that decrease levo absorption
- antacids and polyvalent cations such as iron, calcium, aluminum, mag, multivitamins etc. sevelamer, sucrafate: sperate by 4 hours
- sodium polystyrene sulfonate and patiromer (veltassa)
- lanthanum: separate doses by 2 hrs
hyperthyroidism
T4 high
TSH low
graves’ disease is autoimmune
monitor 4-6 weeks
symptoms of hyperthyroidism
heat intolerance, increased sweating
weight loss
insomnia
tremor
thinning hair
agitations, anxiety, nervousness
goiter (possible)
thionamides are
inhibit synthesis of thyroid hormones by blocking the oxidation of iodine in the thyroid glad
PTU also inhibits peripheral conversion of T4 to T3
propylthiouracil (PTU)
Methimazole (tapazole)
PTU
propylthiouracil
boxed warning: severe liver injury and acute liver failure
preferred 1st trimester of prego due to methimazole cause fetal abnormalities
Dile, agranulocytosis
PTU preferred in thyroid storm if methimazole is not tolerated
methimazole
tapazole
drug of choice due to lower liver damage
prego: PTU preferred in the 1st trimester, methimazole can be used in 2nd and 3rd trimester to avoid liver tox
Iodides
temporarily inhibit secretion of thyroid hormones T4 and T3 will be reduced for several weeks but effect will not be maintained
potassium iodide and iodide soutoin (lugol’s solution)
saturated solution of potassium iodide (SKKI, thyroSafe)
symptoms of thyroid storm
fever
tachycardia
tachypnea
agitation
delirium
dehydration
profuse sweating
psychosis
coma
