NeoMercazole Special Precautions

As fatal cases of agranulocytosis with carbimazole have been reported and early treatment of agranulocytosis is essential, it is important that patients should always be warned about the onset of sore throats, bruising or bleeding, mouth ulcers, fever, malaise and should be instructed to stop the drug and to seek medical advice immediately. In such patients, blood cell counts should be performed immediately, particularly where there is any clinical evidence of infection. Following the onset of any signs and symptoms of hepatic disorder (pain in the upper abdomen, anorexia, general pruritus) in patients, the drug should be stopped and liver function tests performed immediately.
Early withdrawal of the drug will increase the chance of complete recovery.
NeoMercazole should be used with caution in patients with mild-moderate hepatic insufficiency. If abnormal liver function is discovered, the treatment should be stopped. The half-life may be prolonged due to the liver disorder.
NeoMercazole should be stopped temporarily at the time of administration of radioiodine.
Patients unable to comply with the instructions for use or who cannot be monitored regularly should not be treated with NeoMercazole.
Regular full blood count checks should be carried out in patients who may be confused or have a poor memory.
Patients with rare hereditary problems of galactose intolerance, the Lapp lactase deficiency or glucose-galactose malabsorption should not take this medicine.
Precaution should be taken in patients with intrathoracic goitre, which may worsen during initial treatment with NeoMercazole. Tracheal obstruction may occur due to intrathoracic goitre.
The use of carbimazole in non-pregnant women of childbearing potential should be based on individual risk/benefit assessment (see Use in Pregnancy & Lactation).
There is a risk of cross-allergy between carbimazole, thiamazole and propylthiouracil.
Carbimazole may cause white cell disoders such as neutropenia and agranulocytosis, which may be fatal if treatment with carbimazole is not stopped promptly. These reactions usually occur during the first 3 months of therapy, and in most cases, are reversible on stopping treatment. Since agranulocytosis can develop very rapidly, periodic leucocyte counts alone may not be effective in the early detection of these reactions.
During treatment with Carbimazole: The patient should be asked to immediately report signs and symptoms suggestive of infection eg sore throat, fever and mouth ulcer.
A white cell counts should be performed if there is any clinical evidence of infection.
The drug should be stopped promptly if there is clinical or laboratory evidence of neutropenia.
Effects on ability to drive and use machines: The effect on the ability to drive and use machines is not known.