Hazardous Herbs
Some people believe that all herbal products are safe. This is far from true. Although this is not a complete list of unsafe plants, those mentioned deserve special attention.
The following herbs are dangerous and should not be used as remedies.
Plants and Potential Danger
Borage Harmful in large doses; may cause liver damage and cancer
Broom Toxic; diuretic
Chaparral May cause illness; banned in the United States
Coltsfoot May cause cancer
Comfrey May cause liver damage and cancer (but not through
external use)
Foxglove Potent heart toxin
Pennyroyal The essential oil may cause convulsions in large doses; possibly harmful to pregnant women
Pokeweed May cause respiratory paralysis and convulsions
Plant and Potential Danger
Rue May make skin more susceptible to damage from sunlight
Sassafras May cause cancer
The following herbs are potentially dangerous and should be used with caution.
Plant and Potential Danger
Aloe vera The juice can be a powerful laxative when used internally (gels labeled for internal use do not have this effect)
Ephedra Should not be used by people with heart conditions, high blood pressure, diabetes or thyroid disease
Juniper Should not be used by women who are pregnant or people with kidney disease
Licorice Exessive amounts may cause fluid retention and high blood pressure
Yohimbe Side effects include nausea, vomiting, high blood pressure, palpitations, insomnia and tremors