Anti-thyroid

Question 1

Carbimazole

indication

Answer 1

• Hyperthyroidism
• Hyperthyroidism (blocking-replacement regimen) in combo with levothyroxine
  *

Question 2

Carbimazole

MOA

Answer 2

• Carbimazole, a thionamide, is a pro-drug which undergoes rapid and virtually complete metabolism to the active metabolite, thiamazole also known as methimazole
• The method of action is believed to be inhibition of the organification of iodide and the coupling of iodothyronine residues which in turn suppress the synthesis of thyroid hormone

Question 3

Carbimazole

Warnings

Answer 3

• Increased risk of malformation- strong advice on contraception
• Increased risk of pancreatitis- immediately stop if this occurs
• Neutropenia/agranulocytosis- (Sore throat, mouth ulcers/signs ofinfection. WCC)
• Severe blood disorders

Question 4

Carbimazole

Adverse effects

Answer 4

• Blood- Bone marrow suppression (neutropenia, eosinophillia, leucopenia and agranulocytosis), haemolytic anaemia
• Immune system- angioedema and multi-system hypersensitivity
• Severe cutaneous adverse reactions (SCARs)
• Hepatic disorders
• Insulin autoimmune syndrome- pronounced drop in BG
• Pancreatitis

Question 5

Carbimazole

Interactions

Answer 5

• Digoxin- Carbimazole can increase dig levels

Question 6

Carbimazole

Patient counselling

Answer 6

• Warn patients to seek medical attention immediately if sore throat, mouth ulcers, bruising, fever, malaise develops
• Encourage effective contraception to women of child bearing age