This isn't a comprehensive list, but it includes all the cautions I've been able to find for herbs that I have worked with. I'd suggest that you proceed with care every time you consider using a herb you're not familiar with. Often there are differences of opinion, and a herb that one author considers safe may be regarded with extreme caution by another. Since there are so many wonderful herbs that can address any particular condition, it's best to avoid any that are controversial and consult at least two or three good texts before you start to take anything new. - Bob

Black Cohosh: Avoid in pregnancy. Do not exceed stated dosage or symptoms of poisoning could result.

Black Raspberry: Avoid in early pregnancy (uterine stimulant). Recommended by some authors for toning the uterus in the last two months of pregnancy only.

Blue Cohosh: This herb can irritate mucous membranes, and the fresh herb can cause dermatitis. Children have been poisoned by eating the berries.

Borage: Considered safe by all other authors, Weiner (1994) indicates that the lasiocarpine in Borage has been linked to liver damage and cancer in animals. Studies of its effects on humans are not yet available. Not included in any preparation I make for others.

Burdock: Monitor dosage. Transient toxaemia can occur with rapid cleansing.

Cascara Sagrada: Not for use in cases where constipation is caused by bowel tension.

Chamomile: Do not use the essential oil in pregnancy. The herb can cause contact dermatitis.

Cinnamon: Avoid therapeutic doses in pregnancy. Do not use in feverish conditions.

Coltsfoot: Some studies indicate carcinogenic activity, though the risk is low for small doses. See Mills, p. 480, for further details. Not included in any preparation I make for others.

Comfrey: Some studies indicate carcinogenic activity, though the risk is low for small doses. See Mendell p. 74 or Mills, p. 545 for further details. Not included in any preparation I make for others.

Damiana: Not for those with Irritable Bowel Syndrome.

Ginger: Avoid in pregnancy.

Hops: Avoid in depression.

Mint: Do not use with children for more than one week at a time. For adults, it is best to take a few days off after using mint for a week to 10 days, or heart palpitations could result. Mint should not be used when breastfeeding.

Motherwort: Avoid in pregnancy. (Uterine stimulant)

Oat Straw: Decant for those who are gluten sensitive (including some with multiple sclerosis).

Parsley: Avoid in pregnancy.

Sage: Avoid in pregnancy. Not for use by epileptics.

St. John's Wort: Taken in large doses and mixed with skin exposure to the sunlight, this herb can cause dermatitis. Contact dermatitis can also result from handling the fresh plant.

Thyme: Avoid in pregnancy.

Yarrow: In some (rare) cases Yarrow can cause allergic skin responses. Avoid in pregnancy (uterine stimulant).

If you are aware of any cautions for these herbs that are not listed here, please contact me by e-mail.

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