Hello and welcome - Some patients do end up going hypothyroid after a course of antithyroid medications like carbimazole. (It happened to me after a similar drug, methimazole.) I don't think it's fully understood why - could be due to blocking antibodies. We're fellow patients, not docs, so if your appointment is a few weeks away, I would really encourage you to contact your doctor's office ASAP to go over the labs and see if they recommend a prescription for replacement hormone.
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