Mrs Jones is a 30 years old and presented to the hospital 72 hours ago with palpitations and shortness of breath. She was admitted and found to be suffering from Hyperthyroidism and was commenced on both Carbimazole and Propranolol, with an out-patient appointment arranged. Her palpitations are less bothersome and breathlessness has resolved. She has come to see you as she needs more Carbimazole.
Which of the following statements about Carbimazole is most correct?