Drugs and the Endocrine System Flashcards
Thyroid disease, reproductive steroids, corticostercoids, pituitary hormones, calcium metabolism, osteoporosis and insulin are all related to which system?
The endocrine system
Hormones have widespread and diverse effects. What implications does this have for the management of endocrine disorders?
They are difficult to treat
1 in 13 people have issues with me. I can be hyper or hypo and I am related to T3 and T4. What am I?
Thyroid disease
The CNS, CV system and metabolic rate are all affected by which hormone disease?
Thyroid disease
What disease is linked to slow speak, lethargy, hyporeflexia (CNS), hypotension, bradycardia, anemia (CV), weight gain, low body temperature and intolerance to cold?
HYPOthyroidism
What is goitre?
A massive, noticeable thyroid gland
Do people with overactive or underactive thyroid get goitre?
Both.
In underactive this is because a lack of iodine leads to insufficient T3/T4, negative feedback is disrupted so it becomes bigger to try and compensate.
In overactive, antibodies are produced that activate TSH, which increases the size and function of the gland
What is Graves’ disease?
The most common form of hyperthyroidism.
Where antibodies stimulate thyroid cells.
What drugs can we use to treat hyperthyroidism?
Carbimazole and propylthiouracil
Before medical treatment, what can a patient try and do to regulate hyperthyroid issues?
Limit iodine (salt) intake - as this is used to produce thyroxine.
Which drug is taken to inhibit the synthesis of thyroxine, is absorbed at the gut to be converted at the liver to active form, is excreted in the urine and has a short 1/2 life?
Carbimazole
If a pregnant woman is taking Carbimazole, what are the potential side effects?
It could cross the placenta/into breast milk causing neonatal hypothyroidism
What are possible side effects of carbimazole?
Nausea, allergic rash, agranulocytosis, insomnia
As part of what type of treatment/method is carbimazole given?
Block and Replace.
Lots is taken at first, then the dosage is reduced so some thyroxine can be produced - but lack of thyroxine is replaced with synthetic thyroxine
How long does it take carbimazole to become effective?
4-6 weeks. It cannot get rid of thyroxine that has already been produced, it can only stop new thyroxine being produced.
For what condition is levothyroxine or triiodothyronine prescribed? And what are they substituting?
HYPOthyroidism
LevO = T4
TriiO = T3 (for more severe)
Lithium (depression) and amiodarone (anti arrhythmic) drugs can cause what type of hormone disease?
Hypothyroidism
When would we inject radioactive iodine into a patient?
If someone is severely hyperthyroid. The iodine will collect in the thyroid gland and the radioactive isotope will kill off tissue. This is the last step before resorting to surgery.
What does carbimazole target?
The thyroid gland. It stops it producing thyroxine (T4).
What is levothryoxine used to replace?
T4, thyroxine
What is triiodothyronine used to replace?
T3. This would be used in cases where there has been a dramatic loss of thyroxine, as T3 gives a much quicker response than T4.
What can a patient take to reduce the secondary EFFECTS of too much thyroxin?
Beta-blockers. They dampen the sympathetic nervous system.
Which hormone promotes Calcium reabsorption from the kidney?
Parathyroid hormone
What does calcitonin inhibit?
Osteoclasts and reabsorption from the kidney, resulting in decreased calcium plasma levels
BECAUSE less calcium comes back out of the kidney
tonin = tone = decrease
What does calcitriol (vitamin D3) do?
It increases calcium levels in the plasma by increasing bone mobilisation and reabsorption from the gut
What disease is caused by inadequate calcium intake, deficiency in parathyroid hormone/lack of vitamin D and renal problems?
HYPOcalcaemia
If someone had neuromuscular problems, muscle cramps and later mental deficiency, fits or cataracts, what might they have?
HYPOcalcaemia
When would we give someone Ergocalciferol (vitamin D) and which groups of patients can we not give it to?
People with hypocalcaemia.
We cannot give this drug to people with compromised kidney function however.
(more complicated name - can’t give to compromised patients)
Who can we give calcium glucoronate (as an I.V. infusion) or calcitriol?
Anyone with hypocalcaemia
What disease can cause problems with kidney stones/renal failure and muscle problems/cardiac arrest, that needs urgent attention?
HYPERcalcaemia