What are the 2 main thyroid hormones
T3 and T4
What is the preferred treatment for hypothyroidism and why?
L-thyroxine T4.
T4 is less toxic than T3 (cardiotoxic). It is less expensive and has a longer half life.
What are the issues in relation to T4 and the elderly or renal/liver impaired?
Dose should be monitored and reviewed as the body may not be able to metabolise the drug leaving more unbound T4.
When pt is taking T4 monitor for S/S of OD. What are these?
Tachycardia, HTN, anxiety, insomnia.
When taking T4 what _______ should be tested periodically.
Thyroid function.
What are the 3 options for management of Hyperthyroidism?
1) Anti-thyroid agents - Iodide solutions SSKI
2) Radioactive Isotopes I131
3) Surgery
What are the pharmacological intervention for hyperthyroidism?
Thionamides - PTU (propylthiouracil)
Potassium Iodide (KI)
Beta blockers.
How does PTU work?
It prevents iodine from being used to make T3 and T4.
PTU can cross the ______ during pregnancy. This can result in the baby having ______ _________.
Placenta.
congenital hypothyroidism.
What is Agranulocytosis?
Causes flu-like symptoms due to a low neutrophil count <100/ml). Sudden fever, chills, sore throat, weakness, sore mouth and gums, mouth ulcers and bleeding.
How long before therapeutic range for PTU is met?
3-4 weeks.
When is KI used for those with hyperthyroidism?
Potassium Iodide stops T3+T4 production by oversaturation of the thyroid, which turns off the stimulus. Leads to reduced vascularity of the thyroid so is perfect for use before thyroidectomy.
How do beta blockers help with hyperthyroidsim?
They are a complimentary treatment which alleviates symptoms (tachycardia, anxiety) and reduce T3-T4 conversion.
What are the indications for I131?
Hyperthyroidism or Thyroid cancer.
I131 should not be in close contact with ______ and _______ for ____
children, pregnant people, 1 week.
What is the half life of I131?
8 days
What does I131 do?
Destroys thyroid cells.
KI can leave a _______ taste in mouth. It can also cause ______ to the teeth.
Metallic, staining
True/False: The body cannot make iodine.
True
What is an example of a beta blocker
Metoprolol
___________ is used as a replacement therapy for hypothyroidism.
Thyroxine
The thyroid gland needs _____ to produce __ and ___ that regulate the body _______
Iodine, T3, T4, metabolism.
What drug is used to treat hypersecretion of GH? AKA acromegaly.
Lanreotide (GH antagonist)
What drug is used to treat Growth Hormone Deficiency?
Somatropin (Human growth hormone)
Somatropin is to be administered __or __
IM or SC
When is Somatropin contradicted?
When growth plates or epiphyses are fused.
When Somatropin is taken S/S of ______ _______ and ________ should be monitored.
glucose intolerance, hypothyroidism
What is the action of Somatropin?
Stimulates skeletal growth.
When Lanreotide is take ____ should be monitored.
BGL
Biliary tract obstruction is an adverse event for what drug?
Lanreotide.
What is Desmopressin?
It is used for hyposecretion of ADH. It is an ADH agonist (retain H20).
What is Desmopressin indicated for?
Diabetes Insipidus (low ADH or insensitive to ADH) Haemorrhage short term control of bed wetting
What does ADH do?
Causes the kidneys to reabsorb Na and H20 thus reducing the amount of urine produced and raising blood pressure.
Desmopressin use should be used with caution in those with ______ disorders, due to ____ ____ causing ___
Cardiovascular, fluid retention, HTN.
True/False: Desmopressin is fine to use during pregnancy and breastfeeding.
FALSE.
What are the signs of fluid overload?
Headache, weight gain, N&V.
What is used to treat hypersecretion of ADH? (or SIADH)
Demeclocycline (Tetracycline) (ADH antagonist) Increase fluid secretion.
____ products should not be taken with Demeclocycline.
Dairy
What s the site of action for Demeclocycline?
The collecting tubule cells in the kidneys. It diminishes their responsiveness to ADH.
Should those on Demeclocycline be on a fluid restriction?
Yes. <1L/day.
Who is contradicted to take Demeclocycline?
children under 8yrs and later pregnancy.
What are Goitrogens?
substances that interfere with iodine uptake in the thyroid gland which results in reduced TH production.
What are some examples of Goitrogens?
Strawberries, broccoli, red wine, mustard, etc.
Where is oxytocin produced?
Posterior pituitary gland
What is oxytocin used for?
Induction of labour
Placenta delivery
milk let-down
involution of the uterus
True/false: Oxytocin can cause hypertension.
False. Mothers should be monitored for dose-related hypotension.
Oxytocin in labour increases the risk of ____ _____ and ______ _______
uterine rupture,
cervical laceration
Monitor _____ heart rate during labour when oxytocin is being used.
Foetal
What drugs do you need to be aware of interacting with PTU?
Warfarin, digoxin, Theophylline.
What is another name for hyperthyroidism?
Thyrotoxicosis.
