Thyroid Pharm Flashcards
Hypothyroidism drugs
Levothyroxine LT4
Hyperthyroid drugs
PTU
Methimazole
Potassium Iodide
Radioactive iodide
Propanolol
4 Major thyroid effects
Brain maturation
BMR
Bone growth
Beta adrenergic
LT4 treatment
T4 is converted to T3
Well absorbed orally when fasted (80%)
-Can be reduced by celiacs disease
TSH levels should be monitored
LT4 adverse effects
- ) Cardiac complications
2. ) Reduced bone mineral density (particularly in postmenopausal women)
LT3
Only used for severe hypothyroidism
Why check TSH levels at 4-6 weeks?
Time is required for drug to reach steady state
2 major causes of hyperthyroidism
- ) Graves Disease
2. ) Toxic Nodular Goiter
What is graves disease?
Thyroid ImG bind to TSH receptor and activate it
Propanolol
Relieves adrenergic symptoms
Ex: Palpitations, anxiety, tremor
What drug inhibits peripheral conversion of T4 to T3?
Propanolol
Soft/ symmetrical goiter
Graves disease
Toxic nodular goiter
Enlarged gland containing round masses that produce too much thyroid hormone
Enlarger thyroid with irregular surface
Nodular goiter
What do thioamides do?
Inhibit thyroid peroxidase
Why is methimazole preferred over PTU?
Reveres hyperthyroidism more quickly
Fewer side effects
Taken once per daily
Which patients will use PTU?
Pregnant patients/ breastfeeding because it does not cross the placenta wall as well or into breastmilk
Adverse effects of antithyroid drugs? (3)
- ) Allergic reaction
- ) Agranulocytosis: Decreased WBC count
- ) Sever liver injuries with PTU
( may also cause hypothyroidism, but this can be easily reversed)
After (Blank) months of treatment, half of patients with Graves’
disease go into a remission and drug can be
discontinued
After 12-18 mo treatment, half of patients with Graves’
disease go into a remission and drug can be
discontinued
What does potassium iodide block?
Thyroid hormone synthesis and release
KI effects
1.) Reduced thyroid size
Given to Chernobyl children because quick effects
How does Radioactive iodine work?
Causes mutation and death in cells it penetrates
Causes hypothyroidism
DO NOT USE IN PREGO
