KAVA AND THE LIVER
As with alcohol, caffeine, CBD, THC, oral medications, and herbal compounds, kavalactones (kava’s active compounds) are metabolized in the liver.
The liver is the main organ responsible for processing and clearing kava.
If overloaded (such as mixing kava with medications or alcohol) the liver can become stressed. It’s important to speak with your medical professional about kava intake if you have a preexisting liver condition, consume alcohol alongside kava, or take regular medications.
HEPATOTOXICITY
In the early 1990s and early 2000s reports were released (primarily in Europe) that linked serious liver injury (hepatitis, cirrhosis, even liver failure) with kava supplements.
However, after later investigations, many of these cases were likely due to:
Non-traditional extracts (rather than standardized water-based extracts, these ones use organics solvents like acetone or ethanol)
Use of Aerial Plant Parts- (leaves, stems,peel) rather than just the kava root - these parts contain alkaloids and pipermethystine, which can be potentially hepatotoxic.
Pre-existing Liver Disease- as stated earlier. It’s important to check with your health care professional if you have a preexisting liver condition or if liver conditions run in your family.
Concurrent Alcohol or Medication Use- this can strain liver cells, as it works overtime to break all of these down. Genetic differences in liver enzymes (some people may metabolize kavalactones more slowly).
⭐️ WATER-BASED KAVA EXTRACTS
These extracts appear much safer. Pacific Islanders have used these traditional water-based extracts for decades, and modern clinical trials also use this form (see our Kava for Anxiety Blog that describes the trial outcomes).
In these studies:
🟢 No cases of clinical liver failure occurred.
🟢 Mild, reversible increases in liver enzymes (specifically alanine aminotransferase and aspartate aminotransferase) were observed in some participants, particularly with longer term use (over 16 weeks).
🟢 After kava was stopped, enzyme levels returned to normal.
In conclusion, mild impermanent liver stress is possible, but serious injury is rare with proper preparation and moderate dosing. For example: 250mg kavalactones daily for <8 weeks should keep you in the good-to-go zone).
WARNING SIGNS
Listen to your body, and keep an eye out for these warning signs. If they appear, stop your kava consumption and seek assistance from a healthcare provider for liver function tests.
🟡 Yellow skin or eyes (jaundice)
🟡 Dark urine, pale stools
🟡 Unusual fatigue
🟡 Right-upper-abdominal pain
THE BOTTOM LINE
Yes, kava liver risk exists, but it is uncommon. Especially, when traditional root-only, water-based forms are used in moderation.