AACE, TES, and ATA: Joint Position Statement on the Use and Interchangeability of Thyroxine Products
Best Physician Practices:
Patients should be maintained on the same brand name levothyroxine product. If the brand of
levothyroxine medication is changed, either from one brand to another brand, from a brand to
a generic product, or from a generic product to another generic product, patients should be
retested by measuring serum TSH in six (6) weeks, and the drug reiterated as needed. Since
small changes in levothyroxine administration can cause significant changes in TSH serum
concentrations, precise and accurate TSH control is necessary to avoid potential adverse
iatrogenic effects.
Best Patient Practices:
Use the same brand of thyroid medication throughout your treatment. Thyroid disease often
requires lifelong therapy and is best managed with consistent and precise treatment with the
same brand of thyroid hormone. Your doctor may change your dose of thyroid hormone, but
the brand of your thyroid hormone medication should always stay the same.
When you go to the pharmacy, do not change the brand of your thyroid medication without
checking with your doctor. You should not change from one brand of thyroid medication to
another, from your brand of thyroid medication to a generic product, or from one generic
product to another without first checking with your doctor. Repeat blood tests and visits to
your doctor may be required, and your dose may need to be readjusted if your thyroid
medication is changed, or if you switch to a generic product.
Thyroid disease often requires lifelong therapy and is best managed with consistent and
precise treatment. Do not change the brand of your thyroid medication without checking with
your doctor. If the pharmacist suggests changing brands or recommends a generic product,
you should also check with your doctor. Your insurance company or state aid program may
not pay for the cost of a brand name drug or charge a higher co-payment if you want a
specific brand name drug. Repeat blood tests and visits to your doctor may be required, and
your dose may need to be readjusted if your thyroid medication is changed to a different
brand, a generic product, or a different generic product.