Thyroidism

Question 1

Hypothyroidism is

Answer 1

underproduction & secretion of thyroid hormones.

Question 2

Hypothyroidism signs and symptoms

Answer 2

fatigue, weight gain, constipation, menstrual irregularities, depression, dry skin, intolerance to the cold, and reduced body and scalp hair

Question 3

Hypothyroidism complications

Answer 3

dyslipidaemia, coronary heart disease, heart failure, impaired fertility, pregnancy complications, impaired concentration and/or memory, and rarely myxoedema coma (which is a life-threatening medical emergency)

Question 4

Primary hypothyroidism

Answer 4

thyroid gland + caused by iodine deficiency, autoimmune disease (Hashimoto’s thyroiditis), radiotherapy, surgery or drugs

Question 5

Secondary hypothyroidism

Answer 5

caused by pituitary or hypothalamic disorder

Question 6

Overt hypothyroidism

Answer 6

thyroid stimulating hormone (TSH) levels HIGH + free thyroxine (FT4) levels LOW

Question 7

subclinical hypothyroidism

Answer 7

TSH levels HIGH but FT4 & free tri-iodothyronine (FT3) levels within range
~ In pregnancy, defined as overt based on elevated TSH levels (using trimester-specific reference ranges) regardless of FT4 levels.

Question 8

Overt hypothyroidism management

Answer 8

~ levothyroxine sodium = 1st-line
~ If symptoms persist, even after achieving normal TSH levels, adjusting dose
~ For patients whose TSH level was very high before starting treatment or who have had a prolonged period of untreated disease, the TSH level can take up to 6 months to return to the reference range.

Consider measuring

Question 9

Monitoring requirements ~levothyroxine
(Primary hypothyroidism)

Answer 9

TSH levels every 3 months until stable, then yearly thereafter.
~ Monitoring free thyroxine (FT4) symptoms of hypothyroidism persist after starting levothyroxine.

Question 10

Food and lifestyle & levothyroxine

Answer 10

Food, including dietary fibre, milk, soya products, and coffee, might decrease absorption of levothyroxine

Question 11

MHRA & Levothyroxine

Answer 11

if patient reports symptoms after changing to different tablet of levothyroxine = thyroid function test
~ if patient persistently symptomatic, whether they are biochemically euthyroid or have evidence of abnormal thyroid function, consistently prescribing a specific levothyroxine tablet known to be well tolerated by patient should be considered
~ If symptoms or poor control of thyroid function persist despite adhering to specific tablet, consider prescribing levothyroxine in oral solution formulation.