Carbimazole
Uses of Carbimazole
Carbimazole is commonly used in the treatment of Graves disease, hyperthyroidism and toxic nodular goitre.
How Carbimazole Works
Carbimazole is an antithyroid agent and it works by arresting the production of thyroid hormones. It is metabolized to thiamazole through inhibition of the organification of iodide and the coupling of iodothyronine residues.
Side Effects of Carbimazole
Fever, Headache, Nausea, Skin rashes, Arthralgia, Mild gastric distress, Pruritus
Warnings
Kidney Safe If Prescribed
There is limited data on the safety profile of Carbimazole on the kidney. It is fairly safe to use this drug in patients with renal impairment. However, kidney disorder might prolong the half-life of Carbimazole.
Alcohol Safe
It is safe to consume alcohol while on Carbimazole.
Pregnancy Not Safe
There is evidence of fetal risk based on human studies, but potential benefits may necessitate the use of Carbimazole in pregnancy despite the risks. The lowest effective dose should be administered if required. This is often discontinued three to four weeks before term, to reduce the risk to the fetus. Carbimazole can cross the placenta but with adequate dose and thyroid status monitoring, studies have found that neonatal thyroid abnormalities are not shown. Occurrence of congenital malformation is found to be greater in children of mothers with untreated hyperthyroidism as compared to treated.
Driving Generally Safe
Carbimazole usually does not affect the ability to drive. Do not drive unless you are feeling well.
Liver Limited Data
In patients with underlying mild-moderate hepatic insufficiency, Carbimazole should be used with caution. The treatment must be stopped when the liver function test is found to be abnormal. This is because liver disorder might extend the half-life of Carbimazole.
Lactation Limited Data
Carbimazole is excreted in milk and if treatment is continued during lactation the patient should not continue to breast-feed her baby.
Frequently Asked Questions
Written by Dr Sri Viknarajan, MD (Universiti Hasanuddin, Indonesia)
Reviewed by Dr Nur Syuhada binti Zulkifli, MD, Universiti Kebangsaan Malaysia (UKM).
