Levoxyl is manufactured by King Pharmaceuticals, Inc. In the past, there were no generic versions of levothyroxine that were considered equivalent to Levoxyl, even though Levoxyl is a relatively older medication. However, several generic versions have since been shown to be equivalent to Levoxyl.
Past Problems With Generic Levoxyl
Some people are unaware that the U.S. Food and Drug Administration (FDA) has never approved many prescription medications (usually older medications). Almost always, these medications were already around before many of the laws and regulations were established. Levoxyl, as well as all other levothyroxine medications, were all unapproved drugs until recently. Because the FDA did not approve these medications, there was no way to know if any of these products were equivalent.
A few years ago, the FDA required all levothyroxine products to obtain FDA approval. This involved certain studies that determined whether any of these medications were equivalent (or not equivalent) to each other.
The FDA has determined that many of the available levothyroxine products are equivalent to Levoxyl, meaning that they should be as good as Levoxyl. You may find old information on the Internet or from healthcare providers who are behind on this information stating that Levoxyl is not equivalent to other levothyroxine products, but this is not true anymore.
Keep in mind, however, levothyroxine is a "narrow therapeutic index" medication, which means that tiny changes in the dose can result in large changes in the body. As a result, most healthcare providers recommend that you stick with one brand of levothyroxine, if possible.
If you do need to change brands, it is a good idea for your healthcare provider to do blood tests often to make sure that your dose does not need to be adjusted.