Borage
Potential for hepatotoxicity and veno-occlusive disease due to toxic pyrrolizidine alkaloids. Can obtain alkaloid-free preparations.
Calamus
May contain beta-isoasarone, which is carcinogenic and also associated with nephrotoxicity and convulsions
Chaparral
Acute hepatitis, kidney and liver failure
Coltsfoot
May contain pyrrolizidine alkaloids which can cause hepatotoxicity and veno-occlusive disease
Comfrey
Hepatotoxicty and veno-occulsive disease
Ephedra
Increased blood pressure, arrhythmias, psychosis and heart failure
Germander
Hepatitis and liver cell necrosis
Kava
Hepatotoxicity and liver failure
Golden ragwort
May contain pyrrolizidine alkaloids which can cause hepatotoxicity and veno-occulsive disease
Sassafras
Hallucinations, vomiting, tachycardia, stupor, paralysis, diaphoresis and hot flushes (amounts used in food are safe)
Source: Complementary and Alternative Therapy: Charle Maritz, Sharon Byrne and Vivian Pribram (2010)
