Do You Know What Supplements Your Patients Are Using?

Hansa Bhargava, MD


October 31, 2016

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Hi. I'm Dr Hansa Bhargava, medical editor for Medscape andWebMD. Today we'll be talking about supplements. As Americans have become more proactive about managing their own health, the supplement market has boomed. Today, it's an $18 billion industry growing at a rate of about 5% each year.[1] Because the US Food and Drug Administration (FDA) doesn't regulate dietary supplements like it does drugs, consumers often have a difficult time knowing whether the products they buy are safe or effective. Often, they're neither. In fact, many over-the-counter supplements contain ingredients that have little benefit and may be potentially harmful. Some of these ingredients have been linked in studies to liver damage, cancer, arrhythmias, and even death.[2,3,4,5]

Because of this booming industry, more and more patients may ask about supplements or be taking them. Here are a few supplements that you should strongly recommend your patients not use.

Aconite. Although aconite has been used as a homeopathic herb to manage inflammation, arthritis, and gout, it's a known poison. The roots contain alkaloids that are toxic to the heart, nervous system, and gastrointestinal tract. People who have ingested aconite in doses as small as 1 g of the plant can present with a combination of symptoms, including nausea, vomiting, abdominal pain, diarrhea, and even muscle weakness and paresthesias. Cardiac manifestations include arrhythmias, and the main causes of death are refractory ventricular arrhythmias and asystole.[6]

Caffeine powder. This supplement ingredient is marketed in bulk to athletes to boost energy and burn fat, but the FDA warns that pure powdered caffeine is a strong stimulant that can be deadly even in small amounts.[7] Symptoms of overdose include those typical of caffeine, including tachycardia, vomiting, diarrhea, seizures, and even death.

Comfrey. Extracts made from the dried leaves and roots of the comfrey plant are used to treat inflammation and heal wounds. When taken by mouth, however, comfrey is hepatotoxic and can lead to liver failure.[8]

Green tea extract. This is very popular nowadays. Green tea, which is high in antioxidants called flavonoids, has been well researched for its health benefits. Extracts made from green tea, however, are advertised to do everything from promoting weight loss to preventing cancer. Although green tea is perfectly safe as a beverage, its extract has been linked to liver damage as well as symptoms such as heart palpitations, nausea, vomiting, and headaches.[2] It is also important to note that green tea can interact with a large number of medications, so be sure to ask patients if they drink it regularly.

Kava. This root also seems to be popular. It is found in the South Pacific and has been used in folk medicine to treat everything from insomnia and anxiety to the symptoms of menopause. Although there may be some health benefits to kava, the FDA warns that this supplement can cause severe liver damage and potentially liver failure.[9] Kava supplements have also been linked to several reports of dystonia and may interact with drugs used to treat Parkinson disease.

Red yeast rice. This staple of Chinese cuisine is made by fermenting yeast over red rice. Because red yeast rice contains compounds like monacolin K, which are similar to ingredients in statins, it's sold as an LDL cholesterol–lowering supplement. The downside is that these supplements can cause the side effects of statin drugs, such as muscle pain, weakness, and liver damage. When taken together with statins, red yeast rice can magnify these side effects. Some red yeast rice supplements are contaminated with the toxin citrinin, which has been linked to kidney failure.

Yohimbe. Made from the bark of a West African tree, yohimbe is marketed to men as an erectile dysfunction (ED) remedy. Whether it works is still unknown because trials on the herb are lacking. Better known, however, are the side effects that yohimbe can produce, which include tachycardia, anxiety, dizziness, hypertension, insomnia, nausea, and vomiting. Yohimbine hydrochloride is available by prescription, but it is not FDA approved for treatment of ED.

These are just some of the supplements that are out there. Our patients should know that supplements aren't necessarily safe just because they're marketed as "natural." They often contain ingredients that can be dangerous on their own, and they're even riskier when taken together with certain prescription medicines. The best advice is to have patients check with you before they take any supplements and to steer them away from any products with unproven benefits and uncertain safety.


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