In an effort to maintain or improve good health, many of us - almost half the population of the United States according to some reports - take herbal supplements such as echinacea, garlic, ginseng, gingko biloba, and St. John's wort. However, if you are being treated for cardiovascular disease, these agents can conflict with your medication and could result in some rather serious side effects.
A 2001 review of the data that exists from trials done with complimentary and alternative medications (CAMs), authored by Dr. Atul Aggarwal of the Cardiology Unit, University of Vermont, was published in Coronary Artery Disease. In it, he warns of possible adverse reactions for people who are taking CAMs in addition to prescription cardiovascular medications.
Let's start with garlic - taken regularly by millions of people around the world for a variety of reasons including its potential ability to lower cholesterol, and help prevent atherosclerosis. Atherosclerosis is a term that describes a dangerous buildup of sticky plaques inside the arteries. This buildup, if left untreated, can pave the way for stroke, among other things. According to the data reviewed in the article garlic is effective in decreasing the buildup of platelets within the arteries, although the level of effectiveness varies. While this effect may seem like a good thing, it could increase the risk of bleeding in people who are taking antiplatelet medication such as aspirin, clopidogrel, and glycoprotein IIb-IIIa inhibitors. Myocardial infarction was cited among the possible side effects. There is also a risk of excessive bleeding following surgery and stroke.
Ginseng, often used as an immune stimulant and potential antidiabetic agent, has a side effect profile that includes hypertension. This can adversely affect medications that lower blood pressure such as diuretics. The article states that the use of ginseng should be avoided if you are taking warfarin, heparin, or aspirin.
What about gingko biloba? Rumored to improve memory, it has been used in traditional Chinese medicine for centuries to treat a number of complaints. And there are clinical trial data to show that a certain type of gingko biloba is able to help stabilize people with dementia, in terms of cognitive and social functioning. However, it can also interfere with platelet activity and should not be used in conjunction with aspirin or anticoagulants.
Moving right along, we have St. John's wort. Most people use it to help them sleep and fight off depression. However, if you are taking calcium channel blockers, lidocaine, quinidine, amiodarone, or cyclosporine, you should most likely not be taking St. John's wort, as it can interact with these medications. Apparently, to date, no incidence of interactions with warfarin have been reported, however, that does not mean to say that St. John's wort should be taken in conjunction with warfarin. Ask your doctor.
In fact, if you are taking any medications for cardiovascular disease, you should always check with your family doctor or cardiologist before taking any other medications - herbal or otherwise.
And finally, we have echinacea. It seems that the flavonoids in echinacea can interfere with medications such as amiodarone, propafenone, cyclosporine, and ibutilide. This interference can cause something called torsade de pointes - described in medical books as a form of ventricular tachycardia. In the simplest of terms - tachycardia is a rapid beating of the heart. This is not a good thing.
Similarly, if you have had a cardiac allograft and are taking cyclosporin, echinacea, being an immune stimulator, may offset the immunosuppressive effects of cyclosporine, which are essential to the success of the allograft.
So, best advice? If you are thinking of taking CAMs, talk to your doctor - even if you don't have cardiovascular disease but are taking prescription medications. It can't hurt.