While I am a firm believer in the health benefits of herbs, caution and safety must still be observed. Just because it is an herb, doesn’t make it safe. Sometimes it is a matter of quantity, sometimes quality, and sometimes how you use it that make the difference. Here are a few that can be hazardous if used without caution.
Use with caution:
Aloe Vera: The juice can be a powerful laxative when used internally. (The exceptions are products labeled for internal use, read the label and follow directions closely).
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 by people with kidney disease.
Licorice: Excessive amounts may cause fluid retention and high blood pressure.
Yohimbe: Side effects include nausea, vomiting, high blood pressure, insomnia, and tremors.
Borage: Harmful in large doses; may cause liver damage.
Broom: Toxic and a diuretic.
Chaparral: May cause illness. This is banned in the US.
Coltsfoot: May cause cancer.
Comfrey: May cause liver damage and cancer, however not through external use.
Foxglove: Potent heart toxin.
Pennyroyal: The essential oil may cause convulsions in large doses. It is also possibly dangerous to pregnant women.
Pokeweed: May cause respiratory paralysis and convulsions.
Rue: May cause skin to be more susceptible to damage when exposed to sunlight.
Sassafras: May cause cancer.