Levothyroxine: a review of clinical and quality considerations

MHRA review of levothyroxine products in response to concerns about potential inconsistencies of different products.



The review started in January 2011 and MHRA reviewed medical and scientific literature to assess:

  • whether there could be differences in the bioavailability (extent/rate of absorption) of levothyroxine between different tablet products and/or batches
  • what clinical implications this may have
  • whether additional controls were needed