Is Westhroid FDA-Approved?
Westhroid, as well as all other
thyroid USP products, has never received U.S. Food and Drug Administration (FDA) approval. Many Web sites imply that Westhroid is an FDA-approved product, but this is simply not the case.
However, this is not necessarily as bad as it sounds. Many prescription medications have never received FDA approval. Almost always, these are old medications that were in use long before the FDA existed or before certain laws and regulations were in place. For instance, phenobarbital (Luminal
®), a prescription
seizure medication, has never received FDA approval.
Synthetic thyroid replacement medications (sold under the name
levothyroxine) were also unapproved until recently. The FDA required each of these medications to perform the necessary studies and seek approval. It is possible that the FDA may require natural thyroid products to do the same in the future.
Until then, the lack of FDA approval for Westhroid may be a cause for concern. For instance, the prescribing information for the drug does not meet the usual FDA standards, since it does not list the possible side effects, except for a few listed with the warnings and precautions.
Westhroid contains thyroid USP, which means that the manufacturer has prepared the medication according to the formulation or "recipe" of the United States Pharmacopeia (a non-governmental organization) and that it should meet certain consistency and potency standards. It is important to note that meeting USP requirements is not the same as having FDA approval.