For example, some people who have taken ginkgo biloba for years have developed serious bleeding problems, including trouble stopping the bleeding from injuries. Another herbal, ginseng, can cause problems if taken with Coumadin (warfarin) or Lanoxin (digoxin). One middle-aged man was taking warfarin to prevent blood clots after heart surgery. He was doing well for many months. But when he started taking the ginseng he purchased in a health food store, his blood tests showed that he could experience serious bleeding. He was told to stop the ginseng. When he did, his blood test results returned to the desired levels without needing to change his dose of warfarin.
Another patient with heart problems had been taking the same dose of digoxin for years. Then, all of a sudden, his blood tests showed that he had too much of the medicine in his blood. This could make the heart beat too slowly. The doctors could not find a reason for this until the man said he was taking ginseng. His blood test returned to normal shortly after he stopped taking the ginseng.
Another problem with herbals is worth mentioning. Unlike traditional medicines, herbals do not have to be tested to make sure they are safe and effective. This limits our ability to know whether they could be harmful and what they can and can't do. It also allows the sellers of herbals to make claims about their use that may or may not be true. As a rule of thumb, herbals starting with the letter "G" can affect bleeding and blood clotting. This includes garlic, ginseng, gingko, and ginger.
Unfortunately, we know very little about what herbals can and can't do, or the harm they could cause. There are no rules to guide how herbal medicines are made. In 1998, the government formed The National Center for Complementary and Alternative Medicine to scientifically look at herbal medicines and research is underway.
To use herbals safely:
Get to know your herbals. Learn about the benefits as well as the risks and side effects of the herbals you take. You can get information from your pharmacist, a reliable website (e.g., www.mskcc.org/aboutherbs), or from a book on herbals.
Report herbal use. Don't be afraid to tell your doctors, nurses, and pharmacists about herbals you take, even if you are well. It may change the choice of a medicine your doctor prescribes for you, and allow your caregivers to give you advice on which herbals to stop while taking other medicines. If you become sick, telling your doctor about herbals you take might help to determine the cause of your illness.
Stop before surgery. Some herbals can change the effects of medicines used during surgery or cause you to bleed (especially those that begin with "g" such as garlic, ginger, ginseng, and gingko). Always check with your doctor, but it's a good idea to stop herbals at least 1 week before surgery.
See a doctor. Taking an herbal to treat ongoing symptoms like pain, fatigue, or a persistent rash may seem like a good idea. But don't let it keep you from seeking medical help. Herbals may help relieve symptoms, but not cure the illness. A delay in medical treatment could have serious consequences.