The Village Herbalist

Known Drug Interactions

This information is derived from a number of sources. As studies in this area are relatively new and incomplete, this information may or may not prove to be accurate. Herbs have been used medicinally for thousands of years while many drugs have only come into use in the last five or ten years.

Studies on the safety and efficacy of pharmaceuticals often focus on immediate reactions, not long term damage to the body. According to The Journal of the American Medical Association, adverse drug reactions kill as many as 140,000 people every year. ( Jama 1997, 277(4):301)

Echinacea
Echinacea should not be used with known Hepatoxic drugs, such as Anabolic Steroids, Amiodarone, Methotrexate, and Ketoconazole. However, Echinacea lacks the 1,2 saturated necrine ring associated with hepatoxicity of Pyrrolizidine Alkaloids. It also should not be used with ImmunoSuppressants (eg, CorticoSteroids and Cyclosporine).

Evening Primrose Oil
Evening Primrose Oil and Borage should not be used with AntiConvulsants because they may lower the Seizure threshold. Shankapulshpi, an Ayurvedic preparation, may decrease Phenytoin levels as well as diminish drug efficacy.

Feverfew
NonSteroidal anti-inflammatory drugs may negate the usefulness of Feverfew in the treatment of Migraine headaches. It also may alter bleeding time and should not be used with Warfarin Sodium.

Garlic
Garlic may alter bleeding time and should not be used with Warfarin Sodium.

Ginkgo
Ginkgo may alter bleeding time and should not be used with Warfarin Sodium.

Ginger
Ginger may alter bleeding time and should not be used with Warfarin Sodium.

Ginseng
Ginseng may cause Headache, Tremulousness, and Manic episodes in patients treated with Phenelzine Sulfate. Ginseng should also not be used with Estrogens or CorticoSteroids because of possible additive effects. It also may affect blood Glucose levels and should not be used in patients with Diabetes Mellitus. Ginseng may alter bleeding time and should not be used with Warfarin Sodium.

Hawthorne
Hawthorn may interfere with either Digoxin pharmacodynamically or with Digoxin monitoring.

Kava Kava
Kava when used with Alprazolam has resulted in Coma. Its use is not recommended with any high blood pressure medications. It is not suggested for people with liver problems.

Licorice
Licorice can offset the pharmacological effect of Spironolactone. It also may interfere with either Digoxin pharmacodynamically or with Digoxin monitoring.

Plantain
Plantain may interfere with either Digoxin pharmacodynamically or with Digoxin monitoring.

St Johns Wort
Since the mechanism of action of St Johns Wort is uncertain, use with MonoAmine Oxidase Inhibitors and Selective Serotonin Reuptake Inhibitors is not suggested.

Valerian
Valerian should not be used with Barbiturates because excessive sedation may occur.

Back To Contents

Updated 3/10/08