thyroid Flashcards
thyroid replacement therapy
levothyroxine
levothyroxine target
thyroid nuclear receptor
how does levothyroxine work
synthetic replacement of deficient endogenous thyroid hormone
levothyroxine possible adverse
hyper
who should you be cautious with when giving levothyroxine
elderly patients cardiovascular disease long standing hypothyroidism diabetes panhypopituitarism predisposition to adrenal insufficiency
levothyroxine and thyrotoxicosis
don give of people have this
levothyroxine and diabetes
increase diabetic drugs
Beta-adrenoceptor blockers for hyperthyroidism
propanolol
propanolol target
Beta adrenoceptors
therapeutic effects are through what receptor
β1 receptors
propanolol moa
Inhibits binding of noradrenaline this inhibits activation of adenylyl cyclase enzymes leading to reduced cyclic AMP. This in turn leads to reduced intracellular calcium levels.
aim of propanolol
Reduce contractility (negative intropy), reduce heart rate (negative chronotropy), and BP
propanolol common side effects
Dizziness; Headache, fatigue, cold hands, impotence
where is noradrenalon released from
sympathetic adrenergic neurones
propanolol severe side effects
Hypotension Bronchoconstriction Bradycardia and heart block Hypoglycaemia Peripheral vasoconstriction including exacerbation of intermittent claudication Raynaud’s phenomenon
worry of propanolol and diabetes
may mask hypo symptoms
Thionamides
Carbimazole
Propylthiouracil
Thionamides
Carbimazole
Propylthiouracil
Carbimazole target
Thyroid peroxidase enzyme
Carbimazole moa
Inhibits the iodination of tyrosyl residues in thyroglobulin, inhibits coupling of iodotyrosine molecules
Carbimazole overall effect
Reduces output of thyroid hormones T3 and T4 from the thyroid gland
Carbimazole bad adverse effects
Agranulocytosis, neutropenia
what is prefered to Carbimazole in pragnancy
propylthiouracil
what doe thyroid peroxidase do
converts iodide to iodine
Propylthiouracil binds to
thyroid peroxidase
what is degraded to produce the thyroid hormones
Thyroglobulin
Radioiodine (I131) is used to treat
hyperthyroidism and thyroid cancer
how can Radioiodine (I131) be used for palliative
if the mets take up iodine
how does Radioiodine (I131) work
taken up by thyroid and destroys cells by beta decay
