What serious adverse effect has been reported with kava?

Kava, a plant often used for its calming effects, has been associated with hepatotoxic hepatitis, making it a significant concern among its users. The primary adverse effect stems from kava's potential to cause liver damage, which can be severe and even lead to liver failure in certain cases. This hepatotoxicity is attributed to the presence of kavalactones, the active compounds in kava, which may exhibit toxic effects especially when consumed in high doses or in conjunction with other substances, such as alcohol or certain medications.

Many instances of kava-related hepatotoxicity have been reported globally, prompting health agencies to issue warnings about its consumption. This adverse effect is particularly serious due to the long-term implications it may have on liver health, including the possibility of requiring medical interventions like liver transplants in extreme cases.

The other potential adverse effects listed, such as cardiovascular issues, respiratory failure, and kidney damage, are not as prominently linked to kava use or lack sufficient evidence to warrant the same level of concern as hepatotoxic hepatitis.