Notes of Caution about Booming Herbal Medicine Market

In many developing countries, herbal medicine accounts for up to 80 percent of all treatments, according to the World Health Organization. Here at home, that figure is about 70 percent, creating a market expected to be worth more than $94 billion by the year 2032.

That may see like a natural high, but it comes with a natural headache. While most herbals are safe for most people, some products, including plain old-fashioned chamomile tea, may trigger adverse effects such as allergic reactions. Or they may interact with prescription meds, making it hard for the body to use some drugs while conversely making other drugs stronger than your doctor expects them to be.

Some foods also interact with meds, but the real problem, as one article in the New England Journal of Medicine put it, is that patients are so convinced herbs are safe that they often fail to tell their doctor when something goes awry. Worse yet, herb/drug interaction information is sketchy and hypothetical, drawn from animal studies or other indirect means even though more needs to be known about meds, specifically those with a narrow purpose, such as treating cancer.

As a result, it may be difficult to track the actual incidence of herb/drug reactions That means when something untoward occurs, you and your doctor can have a hard time nailing down an accurate answer of the risk associated with the herb/drug combination.

But help is on the way. As the number of herbal products has grown, researchers have revved up their efforts to compile interaction data. The research is relatively new, so it pays to ask your doctor about all potential reactions—food, drugs herbs—whenever he or she prescribes a med.

More to the point, the National Institutes of Health has zeroed in on some prominent problem plants posing a high risk of potential interactions with certain medications. To summarize their findings:

1. St. John’s wort can speed up the processes that change the drug into inactive substances, leading to a decrease in drug levels in your body. It may also interact with some drugs, including SSRI antidepressants in a different way that increases the risk of serious serotonin-related side effects.

2. There are hints but still uncertainties about whether Asian ginseng might interact with certain medicines, such as calcium channel blockers, and other medicines used for high blood pressure that relax blood vessels and increase blood flow, such as statin medicines used for high blood cholesterol, and some antidepressants.

3. Concentrated green tea supplements can reduce blood levels of some drugs, such as the cholesterol-lowering drug atorvastatin and the beta-blocker nadolol.

4.The herb goldenseal may change the way the body processes a variety of medicines such as the diabetes medicine metformin.

5. People who take medicines with a narrow therapeutic index (meaning that if the amount of the drug is even a little too low or too high, it can cause big problems) should mention herbs to their doctor when she prescribes the med. Bring a written list of everything you take, how often you take each product, and the doses