Drug-Induced Hyperthyroidism

Question 1

What drug commonly causes hyperthyroidism and why

Answer 1

AMIODARONE

High iodine content - hyperthyroidism

Inhibits conversion of T4 to T3 (hypothyroidism

Question 2

Role of AMIODARONE

Answer 2

Anti-arrythmic

Question 3

What elements can cause hyperthyroidism if found in a drug

Answer 3

Iodine

Lithium

Question 4

What are the clinical presentations of drug-induced hyperthyroidism

Answer 4

1. Palpatations
2. Diarrhoea
3. Weight LOss
4. Heat Intolerance
5. Tremors
6. Warm
7. Hyperkinesis
8. Anxiety
9. Diffuse Goitre

DIFFUSE GOITRE and WASTING are the biggest signs

Question 5

In elderly how can drug-induced hyperthyroidism be caused

Answer 5

1. Atrial Fibrillation

2. Heart Failure

Question 6

In children, how can drug-induced hyperthyroidism be caused

Answer 6

1. Excessive height or GR

2. Behavioural problems (ADHD)

Question 7

How is Hyperthyroidism treated

Answer 7

1. PROPRANOLOL (controls symptoms)
2. PROPYLTHIOURACIL (stops conversion of T4 to T3)
3. ORAL Carbimazole and THYROXINE which reduces hypothyroidism risk

Question 8

Why do half of those with Graves’ relapse after 2 years

Answer 8

Discontinue treatment after two years

Question 9

What is the main side-effect of treating hypothyroidism

Answer 9

Agranulocytosis - leads to Low white blood cells count (leukopenia)

Rash (less common)

Question 10

When should drugs stop being given to patients with Graves’ or hypothyroidism

Answer 10

If they get throat, mouth ulcers

Fevers

Question 11

When should radioactive iodine be given

Answer 11

4 days after anti-thyroid drugs have been stopped

Question 12

How long does 131-I take for normal thyroid to function

Answer 12

4-12 weeks after radioactive iodine

Question 13

When can radioactive iodine be contraindicated

Answer 13

Pregnancy and breast feeding

Question 14

Side-effects of giving radioactive iodine

Answer 14

Discomfort in the ne ck and hyperthyroidism initially

Question 15

When should surgery be given to individuals with hyperthyroidism

Answer 15

1. Those with large goitre, poor response to drugs or experiencing severe side-effects from treatment

Question 16

What is subtotal thyroidectomy

Answer 16

Leaves a bit of thyroid (nota ll removed) to preserve function

Question 17

When is subtatotal thyroidectomy given

Answer 17

When patient is euthyroid

Question 18

When is a total thyroidectomy given

Answer 18

Those with large goitre, malignancy in nodule or Graves’

Question 19

What should we do before surgery occurs

Answer 19

Stop antithyroid drugs 10-14 days before

GivePotassium Iodide to reduce vascularity of gland

Question 20

Side-Effectt of surgery for hyperthyroidism

Answer 20

Hypothyroid

Tracheal compression from post-operative bleeding
Laryngeal nerve paslsy (sore throat)
Trnasient hypocalcaemia (removal of PTH gland)

Question 21

How can Hashimoto’s thyroiditis be treated

Answer 21

Levothyroxine therapy to shrink goitre even when patient is not hypothyroid

Question 22

How is a thyroid crisis treated

Answer 22

1. LARGE DOSES OF:
Oral CARBIMAZOLE
ORAL PROPRANOLOL
ORAL POTASSIUM IODIDE
IV HYDROCORTISONE

Question 23

Role of ORAL POTASSIUM IODIDE

Answer 23

Block acutely the release of thyroid hormone from glands

Question 24

Role of IV HYDROCORTISONE

Answer 24

Inhibits T4 to T3

Question 25

Signs of children with hypothyroidism

Answer 25

Slow growth velocity | Poor School performance

Question 26

How are papillary and follicular carcinomas treated

Answer 26

Total thyroidectomy | Ablative radioactive iodine

Question 27

Problem with anapaestic carcinomas

Answer 27

1. Does not respond to radioactive iodine External radiotherapy provides brief respite

Question 28

How to treat medullary carcinoma

Answer 28

Thyroidectomy and lymph node removal

Question 29

How is hypothyroidism treated

Answer 29

Oral LEVOTHYROXINE

Question 30

What should we look out for in patients with ischaemic heart disease who are hypothyroid

Answer 30

Start on lower dose

Question 31

What do we increase the risk of if we give LEVOTHYROXINE

Answer 31

AF and Osteoporosis if we suppress TSH completely

Question 32

How is primary hypothyroidism treated

Answer 32

1. Those titrated until TSH normalises | 2. Check T4 levels 6-8 weeks after dose adjustment

Question 33

Why can't we check TSH levels in secondary hypothyroidism

Answer 33

TSH will always be low

Question 34

What do we monitor in secondary hypothyroidism

Answer 34

T4

Question 35

How do we treat Myxoedema Coma and what people does this usually effect

Answer 35

IV T3 and Glucose infusion Old people - confusion

Question 36

How is myxoedema coma caused

Answer 36

EXTREMELY LOW T4

Question 37

What in blood tests would indicate hypothyroidism

Answer 37

1. Normocytic or microcytic anaemia or microcytic in women due to coeliac's 2. Raised serum aspartate transferase levels 3. Increased serum creatinine kinase levels 4. Hypercholesterolaemia 5. Hyponatraemia due to increased ADH

Question 38

Where is iodine deficiency common

Answer 38

Netherlands, India, Russia and Africa

Question 39

Role of Thyroid peroxides

Answer 39

Production and storage of thyroid hormones

Question 40

Problem with Postpartum thyroiditis

Answer 40

Can be misdiagnosed as postpartum depression (Temporary phase after pregnancy)

Question 41

Four ways hypothyroidism can be drug-induced

Answer 41

1. CARBIMAZOLE 2. LITHIUM 3. AMIODARONE 4. INTERFERON

Question 42

What often causes Goitre

Answer 42

Iodine Deficiency