thyroid disorders

Question 1

what are the Signs and symptoms of hyperthyroidism

Answer 1

• goitre ( swelling of the thyroid gland that causes a lump in the front of the neck)
• hyperactivity
• disturbed sleep
• fatigue
• palpitations
• anxiety
• heat intolerance
• increased appetite with unintentional weight loss
• diarrhoea

Question 2

what is hyperthyroidism

Answer 2

excessive production and secretion of thyroid hormones leading to thyrotoxicosis (an excess of circulating thyroid hormones)

Question 3

what are the risk factors of hyperthyroidism

Answer 3

• smoking
• a family history of thyroid disease
• co-existent autoimmune conditions
• low iodine intake

Question 4

what laboratory results show hyperthyroidism

Answer 4

• Low TSH (thyroid stimulating hormone)
  and
• High FT4 ( free thyroxine) and FT3 (free triiodothyronine)

Question 5

what is the non-drug treatment for hyperthyroidism

Answer 5

Radioactive iodine or surgery (e.g thyroidectomy or hemithyroidectomy which involves removing part of/or all of the thyroid gland)

note drug treatment for hyperthyroidism must be carried out whilst waiting for surgery

Question 6

what is the first choice antithyroid drug for hyperthyroidism

Answer 6

First choice: Carbimazole

• Propylthiouracil considered for those in whom carbimazole is unsuitable

Question 7

what are the main side effects associated with taking carbimazole for hyperthyroidism

Answer 7

• bone marrow suppression (Neutropenia and agranulocytosis)

- risk of acute pancreatitis

Question 8

what are the symptoms that a patient taking carbimazole should report that can indicate bone marrow suppression

Answer 8

report symptoms and signs suggestive of infection, especially sore throat

*note: A white blood cell count should be performed if there is any clinical evidence of infection and stop treatment if there is neutropenia - low white blood cell count)

Question 9

can carbimazole be used for pregnant women with hyperthyroidism

Answer 9

• Women of childbearing potential should use effective contraception during treatment with carbimazole
• Carbimazole should only be considered in pregnancy after a thorough benefit-risk assessment (+ use lowest effective dose)

Question 10

can Propylthiouracil be given for pregnant women with hyperthyroidism

Answer 10

yes it can be given but the blocking-replacement regimen is not suitable. Use lowest effective dose

note: the blocking-replacement regimen is using a high dose of antithyroid drugs (ATD) with levothyroxine (L-T4

Question 11

what Propylthiouracil regimen is not suitable during pregnancy

Answer 11

the blocking-replacement regimen is not suitable

note: the blocking-replacement regimen is using a high dose of antithyroid drugs (ATD) with levothyroxine (L-T4

Question 12

why should you counsel patients taking Propylthiouracil on how to recognise signs of liver disorder

what are the signs of liver disorder

Answer 12

because propylthiouracil can cause hepatotoxicity

signs of liver disorder are:

• anorexia
• nausea + vomiting
• abdominal pain
• Jaundice
• dark urine
• pruritus (itchy skin)

Question 13

what is hypothyroidism

Answer 13

the underproduction and secretion of thyroid hormones

Question 14

what are the symptoms of hypothyroidism

Answer 14

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

Question 15

what laboratory results indicate hypothyroidism

Answer 15

• High TSH (thyroid stimulating hormone)
  and
• Low FT4 (free thyroxine) and FT3 (free triiodothyronine)

Question 16

what are the treatment options for hypothyroidism

Answer 16

first line: levothyroxine

• Liothyronine (either alone or in combination with levothyroxine) but it is not routinely recommended, it is more ideal for severe hypothyroid emergencies

Question 17

what are the symptoms of thyrotoxicosis

Answer 17

• increased heart rate (more than 140bpm)
• tachycardia, arrhythmias
• heat intolerance
• diarrhoea (+ n&v, dehydration)
• seizures (+ psychosis)

Question 18

what is the MHRA advice for patients who experience symptoms when switching between different levothyroxine products

Answer 18

• if a patient reports symptoms after changing to a different tablet of levothyroxine, a thyroid function test should be considered. If a patient is persistently symptomatic, prescribe a specific brand of levothyroxine that is well tolerated for patient
• if still poor control of thyroid function despite adhering to specific levothyroxine tablet, consider prescribing levothyroxine in an oral solution formulation.

Question 19

what can decrease the absorption of levothyroxine

Answer 19

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

Question 20

what happens if the metabolism increases too rapidly after initiating levothyroxine or liothyronine

how do you resolve this

Answer 20

may get hyperthyroidism symptoms such as: diarrhoea, nervousness, rapid pulse, insomnia, tremors

To resolve this:
reduce dose or withhold for 1–2 days and start again at a lower dose.

Question 21

can levothyroxine be used during pregnancy

Answer 21

Yes. Levothyroxine requirement may increase during pregnancy.

Need to make sure mother is stable on levothyroxine as Excessive or insufficient maternal thyroid hormones can harm fetus

Question 22

why should a patient be monitored if they are taking liothyronine and they switch to a different brand

Answer 22

because brands of liothyronine without a UK licence may not be bioequivalent

Question 23

name some medications that can affect thyroid function

Answer 23

• amiodarone (can cause hypothyroidism or hyperthyroidism)
• lithium (can cause hypothyroidism)
• iodine containing medication (cause cause hypothyroidism or hyperthyroidism)