If your doctor suggested that you take two different sleeping pills that have never been tested in combination, would you do it?
If she recommended an energy-booster, but you couldn’t tell from the label what was in the bottle, would you take that?
What if she told you to ingest a medication normally used on the skin – would you want to know it might cause liver failure?
You’d probably answer “No,” “No way,” and “You bet your litigious soul I would.”
But now suppose you’re prowling the aisles in the health food store looking at “natural” remedies? You might grab something and figure, “Hey, this is herbal. It must be safe.”
As a nation, we’ve gone bonkers over alternative or “complementary” medicine, including “dietary supplements,” including herbs. More than one-third of American adults now use herbs and we spend more than $3.6 billion a year for them.
But like someone hopelessly in love, we’re a bit blind. Because herbs are sold – and regulated, by the Food and Drug Administration – as supplements, we don’t think of them as drugs, though we take them to fix or prevent all manner of ills.
This suits many people just fine, including Congress, which in 1994 curbed the FDA’s power to review supplements, including herbs, before they’re marketed.
But while the body politic may like things this way, the body into which we pour these products reacts the same whether something is labelled an herb or a drug. And while many herbs are apparently safe, some – and some combinations of herbs and prescription drugs – clearly are not. Consider:
In the latest of issue of FDA Consumer magazine, the FDA published a short list of herbs it considers “possible health hazards.” One is comfrey, whose leaf and root are used externally for treating bruises but which some people are ingesting for general healing. According to the FDA, which keeps track of adverse reports on herbs and supplements, comfrey can obstruct blood flow to the liver, with possibly fatal consequences.
Varro Tyler, dean emeritus of the Purdue University School of Pharmacy and Pharmacal Sciences, puts it bluntly: “Don’t drink comfrey. . . It should be taken off the market.”
Another risky herb is the stimulant ephedra (Ma huang), which can cause high blood pressure, heart attacks, stroke, and death.
Despite the 1994 law weakening its powers, the FDA still has the authority to yank supplements, including herbs, off the market if it can prove they’re dangerous. It hasn’t done so yet with any supplement, but it’s come closest with ephedra. Last year, the agency proposed dose limits on the active ingredient in ephedra, but so far has not followed up.
Other herbs the FDA lists as dangerous include chaparral, an underground “cure” for cancer that may cause irreversible liver disease; germander, an appetite suppressant that may also cause fatal liver disease; and dieter’s teas that can cause vomiting, constipation, and possibly death.
The FDA is also worried about willow bark, which is marketed as an aspirin-free product but can cause Reye’s syndrome, a potentially fatal disease associated with aspirin use by children; and lobelia, an emetic used to induce vomiting, that may cause cause breathing problems, rapid heartbeat, and possibly coma and death.
Complicating things is the fact that many people take more than one herb simultaneously and combine herbals with prescription and over-the-counter drugs. These combinations pose serious risks, says plant medicine specialist Tyler, who detailed his concerns in September’s Prevention magazine.
For instance:
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Blood thinners. Many herbals – notably garlic, ginkgo, ginger, and feverfew – reduce the ability of the blood to clot, which can help prevent heart attacks and strokes. But if taken with over-the-counter anticlotting drugs like aspirin or prescription drugs like Coumadin, you may bleed too easily. If you’re facing surgery, you should not only stop taking mainstream anticoagulants, but the botanicals as well.
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Diuretics and laxatives. Some herbal laxatives such as senna, cascara sagrada, and aloe make you lose a lot of water and potassium. If you take these remedies for more than a few days, you may be at risk for cardiac arrhythmias. Combining these with diuretics – prescription drugs for high blood pressure – increases this risk. In fact, combining prescription digitalis with diuretics, including the herbals, could even be fatal, warns Timothy Maher, head of the division of pharmaceutical sciences at the Massachusetts College of Pharmacy.
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Sedatives and sleeping pills. Studies show that one herbal sedative, kava, is safe and effective for anxiety and, indirectly, for insomnia; another herb, valerian, works well for many people, too. But there is little data on combining these herbs with each other or with prescription sedatives, antidepressants or alcohol.
For that reason, Tyler says, it’s safest not to mix them. But Dr. Michael Jenike, associate chief of psychiatry at Massachusetts General Hospital, says some people do combine kava with Prozac-like antidepressants. “So far,” he says, “there are no apparent adverse effects, but there may be some risks we don’t know about.”
Combining kava with alcohol is risky, he says. You may become too sedated, as if you combined Valium and alcohol.
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Substances that affect blood sugar. Hundreds of herbals, including bitter melon, dandelion, and prickly pear can lower blood sugar. In theory, if you combine these with insulin, you could wind up with too low blood sugar, which can lead to coma and death. This is less likely if you monitor blood sugar closely.
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Antidepressants. Some people combine the herbal antidepressant St. John’s wort with prescription antidepressants like Prozac. Some people also use St. John’s wort with a diet drug called phentermine, an amphetamine-like stimulant. While the first combination may not be dangerous, the second, at least in theory, could be.
Like other so-called SSRI antidepressants, Prozac works by blocking reabsorption of serotonin, a neurotransmitter, by brain cells. Phentermine may increase serotonin in the blood by blocking its destruction in platelets, says Dr. Richard Wurtman, director of the MIT clinical research center and developer of Redux, a diet drug now off the market.
Last year, when the diet drug combination “fen/phen” was withdrawn from the market because of the risk of heart disease, some dieters switched to “phen-Pro,” a combination of Prozac and phentermine.
But the net effect of taking either fen-phen or phen-Pro may be the same – too much serotonin. That is believed to cause heart damage and a potentially fatal condition called primary pulmonary hypertension, says pharmacist Maher. He, with Wurtman, has shown that phentermine acts in the test tube like a class of drugs called MAO inhibitors, which boost a number of brain chemicals, including serotonin.
“If phentermine really is an MAO inhibitor, it would be potentially fatal to take with Prozac,” says MGH’s Jenike, and in theory that would hold for combining phentermine with St. John’s wort, too. So far, though, he is not convinced that phentermine is really an MAO inhibitor.
And what if St. John’s wort itself acts as both an MAO inhibitor and Prozac-like SSRI? That’s a possibility, says pharmacist Maher. If it’s true, that could make it dangerous to take with drugs like Prozac, Zoloft and Paxil and Effexor. But if St. John’s wort does act as an MAO inhibitor, “one would expect reports of adverse effects if you combined it with these prescription SSRIs,” says Jenike. So far, there have been none.
The bottom line is buyer beware. To the federal regulatory system, there’s a difference between herbs and drugs.
But to your body, there isn’t.
Supplement standards being written
Not long ago, the FDA had the power to force manufacturers of dietary supplements, including herbal remedies, to prove those products were safe.
That changed in 1994, when Congress passed the Dietary Supplement Health and Education Act.
Now a “dietary” product can remain on the market unless the FDA finds clear evidence – not mere suspicion – of harm, which means “people have to be hurt first,” says Bruce Silverglade, director of legal affairs for the Center for Science in the Public Interest, a nonprofit consumer group in Washington.
Also, the law only requires manufacturers to produce supplements in accordance with “good manufacturing practices” in the food industry. Manufacturing standards in the food industry are less stringent than those in the pharmaceutical industry. The FDA is now writing new standards for supplements.
Furthermore, before the law, all health claims on supplements – as on food – had to have FDA approval before marketing. Now, manufacturers can make “structure/function” claims without prior approval. That means they can’t say a product prevents heart disease, but they can say something vague, such as, this product “helps maintain cardiovascular function.”
The herbal industry is aware there have been quality-control problems, says Mark Blumenthal, executive director of the American Botanical Council, a nonprofit educational group based in Austin, Texas.
In fact, the council has developed a chemical analysis system to test products, he says. In one study using this system, the council found that some products that claimed to contain ginseng did not.
In August, the Los Angeles Times reported on a chemical analysis it commissioned on the herbal antidepressant, St. John’s wort: Three of 10 brands tested had no more than half the potency listed on the label, and four had less than 90 percent.
At least two companies are now beginning to analyze the ingredients listed on herbal products.
But sometimes, the problem is that herbal remedies contain adulterants that shouldn’t be there at all. In a recent issue of the New England Journal of Medicine, FDA researchers reported on two cases of serious heart problems traced to supplements contaminated with the powerful heart drug digitalis.