thyroid Flashcards
triiodothyronine
t3
thyroxine
t4
what is more potent t3 or t4
t3
what is active t3 or t4
t4, which is what is monitored and watched in patients
drugs and conditions that can cause hypothyroidism
I TALC I interferons T tyrosine Kinase Inhbitors A Amiodarone L Lithium C Carbamazepine
+Hasimotos+
drugs that can cause hyper or hypothyroid
Interferons and Amiodarone
hypothyroid is
decrease in t4 and increase in tsh
symptoms of hypo
cold intolerance dry skin fatigue muscle cramps voice changes constipation weight gain goiter myalgias weakness depression bradycardia caorse hair/loss of hair menorrhagia (heavier than normal menstrual periods) memory and mental impairment
primary test for function of thyroid
tsh
monitor tsh levels every
4-6 weeks until levels are normal
too high thyroid replacement dose in elderly can cause
afib and fractures
DOC for hypothyroidism
levothyroxine (Synthroid)
other meds for hypothyroid
desiccated thyroid (armour thyroid) liothyronine (cytomel)
cytomel
has
liothyronine
t3
dessicated thyroid has
t3 and t4
levothyroxine has only
t4
levothyroxine full replacement dose
1.6 mcg/kg/day use IBW
what weight to use for levothyroxine
IBW!
if patient less than 50 use
1.6 mcg/kg/day IBW
initial starting dose CAD of levothyroxine
12.5 mcg- 25 mcg
Iv to po levothyroxine
0.75:1
levothyroxine is highly protein bound yes or no
yes
how to take levothyroxine
full glass of water
at the same time each day for consistent absorption
60 min before breakfast!
or at bedtime at least 3 hours after the last meal
levothyroxine tablet colors
orangutans - orange (25) will - white (50) no dye vomit - violet (75) on - olive (88) you - yellow (100) right - rose (112) before- brown (125) they- turquoise (137) become- blue (150) large- lilac (175) proud - pink (200) giants- green (300)
if you become pregnant and on levothyroxine you will likely need to
increase dose
drugs that decrease levothyroxine absorption
antacids iron calcium aluminum magnesium multivitamins cholestyramine orlistat(alli,xenical) sevelamer, sucralafate
seperate doses by 4 hours
estrogen and ssris decrease
levothyroxine
beta blockers amiodarone ptu and systemic steroids decrease
levothyroxine effectiveness
warfain and levothyroxine
increases effect of warfarin
increase in PT and INR
levothyroxine and theophylline
decrease in theophylline
levothyroxine causes an effect on two major drugs
warfarin (increase)
theophylline (decrease)
levothyroxine how soon before breakfast
an hour
hyperthyroidism symptoms
heat intolerance or increased sweating weight loss agitation nervousness irritability anxiety tachycardia,palpitations fatigue muscle weakness insomia tremor thinning hair goiter exophthalmous (protrusion of the eyeballs) diplopia light or absent menstrual periods
autoimmune condition for hyperthyroid
graves disease
antibodies
drugs that can cause hypo
amiodarone
iodine
interferons
what can you use for hyperthyroid symptoms
propanolol any beta blockers
propylthiouracil and methimazole have a boxed warning for
severe liver injury and acute liver failure
PTU preferred in first trimester
warnings with ptu and methimazole
hepatotoxicity
agranulocytosis
DILE
SE with PTU and Methimazole
GI upset
how to take PTU/methimazole
with food to decrease risk of gi upset
which is the DOC ptu or methimazole
methimazole
unless thyroid storm or 1st trimester preg.
if pregnant use PTU in first trimester than switch to
methimazole in 2nd and 3rd trimesters to reduce risk of liver toxicity
what to use after exposure to radiation
potassium iodide (KI) it prevents thyroid cancer
signs and sym of thyroid storm
fever greater than 103 tachycardia tachypnea dehydration profuse sweating agitation delirium psychosis coma
how to treat thyroid storm
PTU SSKI or Lugol soln Beta blocker (propanolol) Steroid (dexamethasone) Cooling (blankets and tylenol)
levothyroxine once pregnant
increase dose by 30 to 50 percent
liotrix has
t4 and t3 in a 4:1 ratio
greater than 60 starting dose
25 to 50 mcg QD
levothyroxiNe
normal saline and use immediately
