Which statement about carbimazole is NOT true?

• A. Blood tests should be carried out every 6 months
• B. TSH monitoring is essential to guide therapy
• C. CBC monitoring is recommended during treatment
• D. Liver enzymes should be monitored during treatment

Answer: (A)

The main idea here is that carbimazole therapy requires regular safety and thyroid function monitoring, not infrequent checks. Regular lab tests are done to catch potential adverse effects early and to fine‑tune the dose as thyroid function changes.

The statement that blood tests should be carried out every six months is not accurate because, in practice, monitoring is much more frequent, especially at the start of treatment. Patients typically have complete blood counts to watch for agranulocytosis, and thyroid function tests (such as TSH with free T4) to guide dosing, at intervals of weeks to a few months rather than every six months. Baseline labs are usually done before starting therapy (including CBC and liver enzymes), and then CBC is repeated regularly (commonly monthly to every few months) while adjusting therapy, with thyroid tests checked every 4–6 weeks until stable.

TSH monitoring is essential to guide therapy because it reflects longer‑term thyroid status and helps confirm that the dosing is bringing thyroid function toward normal, even though TSH can lag behind changes in acute hormone levels. CBC monitoring during treatment is recommended to detect agranulocytosis, a rare but serious adverse effect that can occur with antithyroid drugs. Liver enzymes may be checked as a baseline and monitored if symptoms suggest liver injury or if risk factors are present, given the potential hepatotoxic risk, but routine frequent LFT monitoring in all patients is not necessary in every guideline.

So, the six‑monthly blood test schedule is the part that isn’t aligned with standard practice, making it the NOT true statement.