Hypothyroidism

Question 1

Hyperthyroidism is associated with…..

Whereas hypothyroidism is associated with …..

(Men don’t get hyper!)

Answer 1

Hyperthyroidism is associated with oligomennorhoea, or amennorhoea, whereas hypothyroidism is associated with menorrhagia

Question 2

A 50-year-old woman presents to her GP with lethargy, hair loss, and cold sensitivity.

Routine tests are undertaken, which include the following results:

Thyroid-stimulating hormone (TSH): 8 mIU/l (0.5-5.0 mIU/L)
T4: 2.5 mcg/dL (5-12 mcg/dL)

What does she have and treatment?

Answer 2

Hypothyroidism, Levothryoxine

Question 3

78F tiredness, weight gain and constipation. Her medical history includes heart failure, atrial fibrillation, hypertension and type 2 diabetes. She is on furosemide, atenolol, ramipril, amlodipine, amiodarone and metformin.

On examination, she has dry brittle hair.

Which medication is most likely to have caused this presentation?

Answer 3

Amiodarone

Amiodarone is known to cause both hypo- and hyperthyroidism but more commonly the former

(AND PULMONARY FIBROSIS)

Question 4

Constipation is classically a feature of hypothyroidism

Answer 4

Constipation is classically a feature of hypothyroidism

Question 5

○Hypothyroidism management overview:
* Myxoedema coma - hydrocortisone + levothyroxine
* Subclinical hypothyroidism - watch and wait
* Sick euthyroid - repeat TFT in 6/52

○Thyroxine replacement therapy - levothyroxine
*Starting levothyroxine → Normal dose 50-100 µg
* In > 50 y/o and those with cardiac diseases e.g. angina →25 µg
* For ♀ who become pregnant due to ↑ demand in pregnancy →25-50
* Check TFT in 8-12 weeks: aim to normalise TSH to 0.5 - 2.5

○ Side effects
* Hyperthyroidism due to over treatment
* Exacerbate angina if pt has a BG of angina
* Atrial fibrillation
* Reduce bone density

○ Interactions
* Absorption of levothyroxine is reduced by iron - advise to leave 2 hours apart

Answer 5

○Hypothyroidism management overview:
* Myxoedema coma - hydrocortisone + levothyroxine
* Subclinical hypothyroidism - watch and wait
* Sick euthyroid - repeat TFT in 6/52

○Thyroxine replacement therapy - levothyroxine
*Starting levothyroxine → Normal dose 50-100 µg
* In > 50 y/o and those with cardiac diseases e.g. angina →25 µg
* For ♀ who become pregnant due to ↑ demand in pregnancy →25-50
* Check TFT in 8-12 weeks: aim to normalise TSH to 0.5 - 2.5

○ Side effects
* Hyperthyroidism due to over treatment
* Exacerbate angina if pt has a BG of angina
* Atrial fibrillation
* Reduce bone density

○ Interactions
* Absorption of levothyroxine is reduced by iron - advise to leave 2 hours apart