Does Echinacea Cause Liver Damage?
Some herbs, including echinacea, are associated with increased risk of hepatitis and liver damage. Risks range from increases in liver enzymes (which may be a sign of a more serious liver disease) to acute liver failure.(19, 22, 29)
Acute Liver Failure
There are some reports of acute liver failure thought to be linked to echinacea. Most involved cases of patients using more than one herbal supplement, making it difficult to determine the exact cause.(16, 30)
Autoimmune Hepatitis
Another liver condition believed to be linked to echinacea and other herb use is autoimmune hepatitis (AIH). Because of the possibility that echinacea may cause liver toxicity, experts also caution against its use with drugs that are toxic to the liver, such as:(19, 22)
- Amiodarone
- Ketoconazole
- Methotrexate
- Steroids
It is not known if the herbs cause or even trigger AIH, or if the association is just coincidental. These warnings of potential liver damage may also be because the roots of E. pallida and E. angustifolia contain small amounts of alkaloids. Certain types of alkaloids can damage the liver.(19, 22)
However, the echinacea alkaloids are structurally different than those that can cause liver damage. Additionally, new study evidence refutes the German Commission E's earlier warning against using both E. purpurea and E. pallida for more than eight weeks.(19, 22)
Echinacea's Protective Effects in the Liver
Preclinical research suggests that echinacea may actually help protect the liver and kidneys from toxins. In one study, echinacea protected the liver from the toxic effects of a potent steroid. Echinacea increased beneficial immune cells and counteracted oxidative stress caused by the steroid. In another, Echinacea purpurea protected the liver and kidneys of animals exposed to nitrates, chemicals that are commonly used as food preservatives.(31, 32)
A case report suggests that echinacea may also help treat hepatitis B. The patient was given the herbal formula Echiherb®, containing Echinacea purpurea and quercetin to treat a recurrent respiratory infection. After 6 weeks of treatment, the patient's doctors found that her liver enzymes levels were decreased and her hepatitis stabilized.(33)
The Bottom Line
Case reports indicating a link between echinacea usage and liver damage have not determined definite causation. Still, studies have not conclusively eliminated the possibility that echinacea may be toxic to the liver in some people. And preliminary research suggests echinacea may reduce the beneficial effects of herbs such as milk thistle in the liver. The bottom line is that you should discuss using echinacea with a qualified medical practitioner to assess any possible risk before taking it.(16, 34)