Flavocoxid

Hepatotoxicity

In clinical trials, serum aminotransferase elevations occurred in up to 10% of patients on flavocoxid therapy, but elevations above 3 times the upper limit of normal occurred in only 1% to 2% of recipients. However, there have been several reports of clinically apparent acute liver injury attributed to flavocoxid. Most cases have occurred in women (who are more likely to take flavocoxid). The time to onset has been 1 to 5 months and the pattern of enzyme elevations was usually hepatocellular or mixed. Most cases have been moderate in severity and no instance of acute liver failure or death has been reported. Complete resolution upon stopping flavocoxid has occurred in 2 to 12 weeks. Immunoallergic features have been mild and autoantibodies are not common. At least one instance of recurrence upon rechallenge has been reported.

Mechanism of Injury

Flavocoxid is a proprietary mixture of molecules extracted from plants and it is unclear which component(s) might be responsible for liver injury. The mixture includes extracts from Scutellaria baicalensis (containing the phytochemical baicalin) and Acacia catechu (catechin)), both of which have been implicated in causing idiosyncratic acute liver injury, but the mechanism is unknown.

Outcome and management

No instances of acute liver failure or chronic liver injury have been linked to flavocoxid use and all cases have been self-limited, without subsequent chronic hepatitis or vanishing bile duct syndrome. Recurrence upon re-exposure has been reported and rechallenge should be avoided. There is no information on possible cross sensitivity of hepatic injury with other medications or herbal agents such as skull cap or green tea.

References

References

1. "Flavocoxid".
2. (2010-10-01). "Efficacy and safety of flavocoxid, a novel therapeutic, compared with naproxen: a randomized multicenter controlled trial in subjects with osteoarthritis of the knee". Advances in Therapy.
3. "Flavocoxid Drug Record". United States National Library of Medicine.
4. (1994-01-01). "Acute hepatitis with use of over-the-counter herbal remedies". Virginia Medical Quarterly.
5. (2009-10-01). "The safety of flavocoxid, a medical food, in the dietary management of knee osteoarthritis". Journal of Medicinal Food.