market. Namely, there were issues about product stability, which has a direct impact on the shelf life or the expiration dating of the product, formulation consistency and content uniformity concerns within a given brand, and then there was the issue of bioequivalence. Bioequivalence had never been formally established between brands.
Well, levothyroxine sodium degrades very quickly when it's exposed to light, moisture and oxygen, and when it's combined with a carbohydrate excipient, it undergoes a biphasic degradation process whereby there's a rapid initial decay phase followed by a more gradual degradation phase.
These characteristics have a direct or a negative impact actually on the product's stability. Between 1990 and 1997, there were 10 recalls involving a 150 lots and over 100 million tablets. These recalls ranged from Class 1 to Class 3 and were initiated because of content uniformity, subpotency, and stability failures.
In an attempt to address these issues or these stability problems, many products were manufactured with a stability overage which is very distinct or different than