Hypothyroidism Flashcards
What is hypothyroidism
Underproduction and secretion of thyroid hormones
High TSH (thyroid stimulating hormone) and low free thyroxine (T4)
Who is at risk of hypothyroidism?
Increasing age
Gender (women)
Family history
Thyroid surgery
Radiation therapy
Antipsychotic drugs
Defective thyroid gland
Symptoms of hypothyroidism
Constipation
Weight gain
Cold intolerance
Depression
Hair loss
Fatigue
Bradycardia
What thyroid hormone is considered in pregnancy?
Only TSH since T4 levels are naturally higher in pregnancy
What is the treatment of choice for hypothyroidism
Levothyroxine - synthetic version of t4
How should levothyroxine be taken?
To be taken in the morning at least 30 minutes before breakfast, caffeine-containing drinks or other medicines.
What is the caution with levothyroxine?
Baseline ECG is valuable because changes induced by hypothyroidism can be confused with ischaemia.
What are some side effect cautions with levothyroxine?
If diarrhoea, nervousness, rapid pulse, insomnia, tremors and sometimes anginal pain develops, reduce dose or withhold for 1–2 days and start again at a lower dose.
Can levothyroxine be used in pregancy
Yes
How many hours should be left between calcium products
4 hours
What is another medication used in hypothyroidism
Liothyronine - synthetic version of T3
Why is liothyronine used?
Has a more rapid effect and rapidly metabolised than levothyroxine
Ideal in thyroid emergencies
Why should the same brand of liothyronine be used?
Different brands may not be bioequivalent
If a patient is taking liothyronine, what is the tests that need to be done if the patient is taking it long term
If a patient is taking Liothyronine long-term, thyroid function test should be repeated 1–2 months after any change in brand.
