Ginkgo biloba is one of the most extensively studied herbs in the U.S. and Europe. Ginkgo is a spectacular tree that has been in existence for millions of years. It can live for more than a thousand years, grow to a height of 122 feet and is considered by some to be one of the wonders of the world — a “living fossil.”
Extracts of the leaves of the ginkgo tree have antioxidant and anticoagulant (blood thinning) properties. Antioxidants stop free radical from damaging DNA and other cells.
Studies indicate that Ginkgo may help to keep your memory sharp and improve circulation. It has been used for intermittent claudication to relieve pain in the lower leg after walking due to poor circulation and a variety of other indications.
To avoid excessive bleeding, Ginkgo should not be taken with aspirin-like products, NSAIDs nor with Coumadiin. Ginkgo may reduce the effectiveness of seizure medications, alter blood glucose levels in people taking insulin and cause a spike in blood pressure in those taking certain diuretics.
Billions of dollars are spent annually in the U.S. on over-the-counter products in efforts to maintain or improve health. Many of these dollars are spent on herbal products. These products are derived from plants. They come in a variety of forms besides tablets and capsules. Some are useful, others are worthless. Some are safe, others are potentially harmful. What follows are four more examples of herbal-drug interactions.
Herbal-Drug Interactions
St. John’s Wort (Hypericum perforatum) is a shrubby plant with yellow flowers. This herbal preparation is used for mild to moderate depression. Wort (not to be confused with wart) is derived from an old English word meaning plant.
St John’s Wort has gained increase popularity as an antidepressant since research indicates it’s beneficial and works with less side effects compared to traditional treatment. It has also been used for Seasonal Affective Disorder (SAD — depression starting in the fall/winter and feeling better during the spring/summer, when there’s more daylight).
If you’re taking an antidepressant, be cautious before adding St John’s Wort to your pill box. This combination can cause a dangerous spike in the blood pressure, Serotonin Syndrome (see below).
The herb may decrease the therapeutic effect of digitalis, oral contraceptives and medications for HIV/AIDS patients. The use of this herb with certain antibiotics can result in increased sensitivity to sunlight.
Saw Palmetto is a small berry fruit that the Native Americans used initially as food rather than as a medicine. Much later, people realized the berries could be used for medicinal purposes. Today, it’s high on the list of best-selling herbs for men.
Men use Saw Palmetto mainly to treat benign prostatic hyperplasia (BPH). When the prostate gland is enlarged it constricts the urethra, the tube that empties urine from the body as it passes through the prostate gland. The narrowing of the urethra causes men to complain of urinary frequency, delay onset of urination, night urination and other complaints.
Saw Palmetto may make oral contraceptives less effective, thereby increasing the risk of unplanned pregnancies. It may interfere with blood thinning medication such as Coumadin, aspirin and Plavix.
Kava Kava is a tall shrub that grows in the South Pacific islands. It is known as a ceremonial drink having calming qualities. Some have compared it to alcohol and its relaxing effect. Research supports the effectiveness of Kava to be used on a short term basis to reduce stress, anxiety and to treat restlessness.
Several countries have limited the distribution or banned its use because of the potential harmful side effects. Of primary concern, Kava can cause severe liver damage (hepatitis, cirrhosis) and liver failure necessitating liver transplants. In worst case scenario, it has been implicated in deaths due to liver toxicity.
There’s an increased health risk to persons taking drugs or supplements with similar effects as Kava or those with liver problems. To prevent serious complications, avoid combining Kava with substances such as alcohol, antihistamines, chamomile, sleeping pills and St John’s Wart.
Several countries have banned its use and probably it’s a good idea for you to do the same.
Echinacea is a medicinal plant native to the United State. It is used primarily to shorten the duration of the common cold and other upper respiratory infections. Topically, people have applied this herb as a cream or ointment to treat poorly healing wounds and chronic ulcerations.
This popular herb from the purple coneflower is a relative of ragweed and may worsen your hay fever during the allergy season. Because Echinacea can stimulate the immune system, it can undo the effects of immunosuppressant medication. Therefore, it should not be given to cancer taking immunosuppressants or transplant patients.
Echinacea should not be taken on a daily basis for long periods of time. Some suggest this herb should be cycled on and off for several days every two to three weeks. Pregnant women as well as patients with autoimmune disease should avoid using this herb.
Millions of Americans use herbal products. Allergic reactions, side effects and drug interactions can have harmful consequences. It’s critical to inform your doctor and pharmacist about the medications and over the counter products you are taking. “Natural” does not mean safe!
Glossary
Serotonin Syndrome is a group of symptoms resulting from an increase in the level of the neurotransmitter serotonin. These symptoms can include a worrisome elevation of blood pressure, intense anxiety, tachycardia, confusion and coma.
References
Anticaglia, Joseph R M.D.; Sataloff, Robert M.D.; Hawkshaw, Mary R.N. B.S.N. What Singing Teachers Should Know About Complementary, Alternative and Integrated Medicine; Journal of Singing October, 2005
Blumenthal, Mark et al; The Complete German Commission E Monographs; Therapeutic Guide to Herbal Medicine; 2002
Editors of Pharmacist’s Letter; Natural Medicines, Comprehensive Database; Therapeutic Research Faculty, 2002
This article is intended solely as a learning experience. Please consult your physician for diagnostic and treatment options.