The following are a list of herbs one is well advised to avoid, but which one
still may find with glowing recommendations in certain places. This list
is by no means exhaustive (even when we get a few more in here...).
Coltsfoot (Tussilago farfara).
Liver carcinogen.
The liver is one of your most important organs.
Hepatotoxin. Liver-damaging pyrrolizidine alkaloids are
present and are problematic even with chronic low dose exposure. Avoid
taking it internally.
Ephedra sp.
(This includes stuff
like "Herbal Ecstasy", and the like. I've also seen it listed in herbal
anti-histimines. Has been known to cause death. Can
interact unpleasantly with other drugs, active ingredients in herbals. Just
because something is "natural" doesn't make it good for you. Note also that
many herbal preparations lack information about concentrations of ingredients, if
only because concentrations vary from plant to plant. Ephedra can increase the
heart rate, and induce palpitations. It may also markedly increase blood
pressure. Best to Avoid.
Pennyroyal (Mentha pulegium).
Abortifacient. The level
where a miscarriage can be
expected to be induced is about at the same level that other effects,
including liver damage, convulsions, coma, death, can occur in the mother.
At lower doses, birth defects might be a likely outcome. The tea has too
little of the active ingredient to be likely to induce abortion, although
there is a strong caution concerning liver damage or effects on pregnancy
and fetal development even with the tea.
Sassafras (Sassafras albidum).
Carcinogen
Tansy (Tanacetum vulgare).
The active ingredient, thujone, may be present in from 0-95% of the
oil component of the plant. Dosing, therefore, is exceedingly unreliable.