Side Effects of Herb Supplements

The World Health Organization estimates that, worldwide, 80 percent of people use herbs for at least part of their health-care treatments. In the United States, herbal supplements are not regulated by the Food and Drug Administration, so it's important to educate yourself about possible side effects. Herbs can be powerful remedies, and some of the most popular ones have side effects that can be toxic. Always consult a medical practitioner before taking herbs if you have a medical condition or are on medication.

Echinacea

• Echinacea is used to boost immunity and treat cold and flu symptoms. Some studies show it reduces the chances of catching a cold by more than 50 percent. It does seem to offer some protection and to shorten the duration of colds. But the University of Illinois McKinley Health Center says people with autoimmune diseases like multiple sclerosis, lupus, arthritis, HIV, leukemia, tuberculosis, diabetes or liver disease should not take echinacea. The herb reacts with immunosuppressants and can cause allergic reactions.

St John's Wort

• St. John's Wort is an antidepressant and can be effective for mild to moderate depression. Its side effects are minimal compared to prescription antidepressants, but it reacts with a number of medications so should only be combined under a doctor's supervision. The University of Maryland Medical Center cautions that St. John's Wort can react unfavorably with HIV drugs, birth control pills, blood thinners, any prescription antidepressants and some asthma drugs. It can create extreme sun sensitivity in skin, fatigue, restlessness, upset stomachs and allergic reactions.

Ginkgo Biloba

• Ginkgo is used to improve memory, treat dementia and relieve circulatory problems, especially in the legs. It has been an effective remedy for vertigo and ringing in the ears and it is an antioxidant. Ginkgo thins the blood, so exercise caution if you are taking blood thinners. It has been known to cause headaches, allergic skin reactions and gastrointestinal distress. It also can increase the blood-thinning effects of aspirin.

Siberian Ginseng

• Siberian ginseng has long been used in Russia and China as an adaptogen --- an aid to help the body cope with stress. It is an entirely different plant from American or Asian ginseng. Siberian ginseng has shown some ability to speed relief from colds and flu, reduce herpes simplex outbreaks, restore mental alertness and quality of life in the elderly. Some of these results are anecdotal, and some have held up in preliminary scientific studies. The University of Maryland Medical Center says that side effects of Siberian ginseng might include insomnia, high blood pressure, headache, irregular heartbeat, nosebleeds, drowsiness and vomiting. The herb can react with heart medications, blood thinners and sedatives and should not be taken by anyone who is pregnant.