Comfrey may cause serious allergic reactions. Stop using Comfrey and seek emergency medical attention if you develop difficulty breathing, hives, or swelling of your face, lips or tongue.
Is comfrey an irritant?
When taken by mouth: Comfrey is LIKELY UNSAFE for anyone when taken by mouth. It contains chemicals (pyrrolizidine alkaloids, PAs) that can cause liver damage, lung damage, and cancer.
What are the side effects of comfrey?
Common side effects of comfrey include:
- abdominal distension.
- abdominal pain.
- loss of appetite.
- lack of energy.
- liver enlargement.
- decreased urine output.
- obstruction of small veins in the liver (veno-occlusive disease)
