Is it safe to use oil of oregano with elevated Liver Function Tests (LFTs)?

Safety of Oil of Oregano with Elevated Liver Function Tests

Oil of oregano should be used with caution in patients with elevated liver function tests (LFTs), as there is limited evidence regarding its safety in this context, and some herbal supplements can potentially worsen liver injury.

Understanding Elevated LFTs and Herbal Supplements

• Elevated liver function tests indicate hepatocellular damage or cholestasis, which can be caused by various conditions including drug-induced liver injury, viral hepatitis, alcoholic liver disease, or non-alcoholic fatty liver disease 1.
• Herbal supplements, including oil of oregano, contain chemical compounds that are foreign to the body and require metabolic degradation for elimination, potentially generating hepatotoxic metabolites in susceptible individuals 2.
• Herb-induced liver injury (HILI) shares similarities with drug-induced liver injury (DILI), and both can cause elevated LFTs in susceptible patients 2.

Evidence Regarding Oil of Oregano and Liver Function

Potential Benefits

• Some animal studies suggest that oregano and its components (like carvacrol) may have hepatoprotective effects:
  • Carvacrol has shown protective effects against ischemia-reperfusion injury in rat liver models 3.
  • Dietary oregano administration has demonstrated some ability to alleviate carbon tetrachloride-induced oxidative stress in rat livers 4.
  • Low-dose oregano oil (20 mg/kg) showed protective effects against liver injury in animal models 5.

Potential Risks

• High doses of oregano oil may have adverse effects on immune function, even while providing some liver protection 5.
• Herbal supplements in general can cause idiosyncratic liver injury in susceptible individuals 2.
• The FDA does not strictly regulate herbal supplements like oil of oregano, making quality control and dosage standardization challenging 2.

Clinical Management Recommendations

For Patients with Elevated LFTs:

• Patients with elevated LFTs should exercise caution when using any herbal supplements, including oil of oregano 1.
• If LFTs are significantly elevated (>3 times the upper limit of normal), herbal supplements should be discontinued 1.
• For patients with mild LFT elevations who wish to use oil of oregano:
  • Consider more frequent monitoring of liver function tests (every 1-2 months) 1.
  • Start with lower doses and monitor for any worsening of LFTs or symptoms of liver injury 5.

Monitoring Recommendations:

• Baseline liver function tests should be obtained before starting any herbal supplement in patients with known liver disease 1.
• Monitor for symptoms of liver injury such as fatigue, nausea, abdominal pain, dark urine, or jaundice 1.
• If LFTs worsen after starting oil of oregano, the supplement should be discontinued immediately 1.

Special Considerations

• Patients with pre-existing liver disease should be particularly cautious about using herbal supplements 1.
• Concomitant use of other hepatotoxic medications may increase the risk of liver injury when combined with herbal supplements 1.
• Patients undergoing treatment with immune checkpoint inhibitors or other medications that can cause liver injury should avoid herbal supplements that might compound this risk 1.

Conclusion

While some animal studies suggest potential hepatoprotective effects of oregano components, there is insufficient clinical evidence to establish the safety of oil of oregano in humans with elevated LFTs. Given the potential for herb-induced liver injury, patients with significant liver function abnormalities should avoid oil of oregano until their LFTs normalize or consult with a hepatologist before use.