Side Effects of Herbs and Supplements

Side Effects of Herbs

For thousands of years plants have been used to ease the suffering from every kind of ache and pain. In modern times this practice is known by many names: herbalism, traditional medicinal, folk medicine, botanical medicine, medical herbalism, herbal medicine, herbology, and phytotherapy. See examples of Herbal Remedies here.

This forum explores the side effects and adverse events that result from using herbs and supplements for medicine. These are the countraindications, warnings, drug/herb interactions and side effects that you should be aware of before using these supplements.

Natural health supplements and herbs are added to this list of herbs by request so if you have a favorite, let us know and we will do the research for you.

Herbs and Natural health Supplements

The following table is color coded. A green background indicates no side effects. A yellow background indicates a high number of warnings or side effects. Click on the name of the herb to read about the side effects and warnings.

Herbs/Supplements Number of Warnings Number of Side Effects
Acidophilus 2 3
Aconite 3 6
Agar 5 5
Alfalfa 8 3
Aloe Vera 8 6
Andrographis 4 7
Angelica Root 4 9
Astragalus Root 3 0
Basil 5 0
Bay Leaf 3 3
Bearberry 7 4
Bilberry 8 0
Bitter melon 4 3
Black Cohosh 4 6
Borage Oil 4 3
Boswellia 4 0
Buckthorn 9 9
Burdock root 3 1
Calendula 4 0
Castor Oil 3 5
Catnip 7 6
Cat’s Claw 10 3
Cayenne Pepper 5 6
Chamomile 3 1
Chaparral 2 5
Chia 2 1
Chondroitin 4 0
Chromium 8 7
Cinnamon 6 0
Cloves 2 0
Co-enzyme Q10 9 5
Coffee 10 5
Cola tree 11 4
Coltsfoot 6 3
Coriander 3 1
Creatine 5 2
Cucumber 3 4
Dandelions 6 0
Devil’s Claw 4 8
DHEA 4 15
Echinacea 6 8
Ephedra 12 16
Eucalyptus 12 7
Evening Primrose Oil 7 4
Fenugreek 5 5
Feverfew 2 4
Flax Seed 9 4
Garlic 4 5
Ginger 8 5
Ginkgo Biloba 6 6
Ginseng 10 12
Glucomannan 9 4
Glucosamine 5 8
Goldenseal 13 2
Gotu Kola 3 3
Grape Seed Extract 2 8
Green Tea 9 14
Guarana 18 13
Hawthorn 5 6
Hops 11 3
Horseradish 5 3
Jamaican dogwood 10 2
Jimson Weed 6 22
Juniper 4 3
Karaya Gum 2 0
Kava 11 7
Kelp 5 2
Khat 11 7
Lavender Oil 6 7
Lemon Balm 4 5
Licorice 8 4
Lysine 2 3
Marshmallow 5 0
Melatonin 9 13
Milk Thistle 3 5
Mistletoe 7 5
Myrtle 3 3
Mullein 2 0
Nettle 6 4
Nutmeg – Mace 5 0
Parsley 4 0
Peppermint 2 6
Pill-bearing Spurge 9 4
Pineapple 2 6
Poplar 3 0
Poppy Seeds 3 6
Quinine 9 5
Raspberry 3 2
Rosemary 7 0
Rue 4 4
Sage 6 9
SAM-e 4 11
Saw Palmetto 7 4
Senna 7 4
Soy 18 5
St. John’s Wort 20 6
Tribulus Terrestris 2 2
Thyme 3 0
Turmeric
(Tumeric, Curcumin)
4 0
Valerian 6 10
Vitex Agnus Castus
(Chaste tree)
4 3
Wintergreen 3 8
Witch Hazel 2 4
Yarrow 9 3
Yerba Mate 5 2
Yohimbe 9 13

* A green background indicates no side effects. A yellow background indicates a high number of warnings or side effects.

For questions and answers about the side effects of herbs see the Herb Forum

Last post: August 27, 2017

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