Lidocaine is extensively metabolized in the liver, so drugs that decrease hepatic blood flow (e.g., propranolol) or inhibit CYP1A2/CYP3A4 (e.g., fluvoxamine, ketoconazole, clarithromycin) may elevate systemic concentrations and increase the risk of central nervous system or cardiovascular toxicity
Acetaminophen overdoses, either accidental or intentional, are the leading cause of acute liver failure in the United States, accounting for 56,000 emergency room visits per year
Other research has also identified that abundance of Firmicutes plays a role in altering BBB function and found that the ratio of Firmicutes/Bacteroidetes increased in aging mice as well as the alpha diversity (the mean species diversity), while the BBB function became impaired [96]
The results imply that application of exogenous GABA can feed back to the TCA cycle to promote the carbon and nitrogen cycle
And while no major risks have been documented in these studies, some researchers worry about the potential tumor-growth concern mentioned earlier