If you ingest these drugs unintentionally, you could face a few serious risks, says Pieter Cohen, MD, an assistant professor of medicine at Harvard University and an internal medicine doctor at the Cambridge Health Alliance.
For one, sibutramine, a weight-loss drug, isn't supposed to be available in this country because of its link to heart attacks and strokes, Cohen
The other drugs may seem safer, but only when taken under a doctor's supervision.
These pharmaceuticals could cause dangerous drug interactions with medications you already take, or they might exacerbate underlying conditions.
For instance, men with certain heart problems should not take Viagra, he
Dosing is another concern.
Prescription drugs are manufactured in precise concentrations so that you can always ensure a safe dose.
In supplements, the drug concentrations vary widely.
"So in one batch of supplements, it might be in a dose higher than prescriptions; in the next batch it might be lower," says Cohen
High doses could pose higher risks.
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The big question researchers can't answer: How did these supplements end up on store shelves?
"These are clearly the most hazardous type of supplements out there, and the ones that the FDA
is working the hardest to try to remove," says Cohen
"So the fact that the exact same supplement that the FDA
has issued a recall about reappears months or years later with drugs is just mind-boggling."
It's possible that some of the supplements in the study were manufactured before the recall and weren't properly removed from the market, says Cohen
However, it's also quite possible-and likely, in his
opinion-that the companies kept on making drug-tainted supplements after the recall.
If you take any supplements, check this list for the products found to contain pharmaceuticals.
Avoid anything on this list, even if you can still find it in stores, says Cohen
"The FDA's job is to remove dangerous supplements from the marketplace, and that's not happening as you can see here," says Cohen
should re-test previously recalled supplements to make sure the companies take out the offending ingredients, he
What's more, don't assume that just because something hasn't been recalled, it's automatically safe.
Before you pop any supplement, read the label closely.
Some supplement ingredients have been studied extensively, and the research suggests that they are safe and possibly beneficial.
But be wary of new or strange ingredients, especially in workout, weight-loss, or sex supplements: "It's whenever you start seeing multiple different herbal ingredients listed on the label-these proprietary blends, these cocktails of herbs-that you're going to run into problems," says Cohen