Answer
Combining levothyroxine with antithyroid medicines for hyperthyroidism is not indicated during pregnancy because it requires higher antithyroid doses, and these medicines cross the placenta and can induce hypothyroidism in the infant.
Sources for this answer
- Levothyroxine 25 micrograms TabletsWockhardt UK Ltd · emc · SmPC §4.6 Fertility, pregnancy and lactation · Version 11Document updated
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