Why MDs Avoid Supplements

When your physician asks what medications you are taking, and then follows up with “anything else? Vitamins? Supplements?” PLEASE share everything that you are taking. We don’t ask this to judge your personal choices, nor because we know every ingredient- on the contrary. Natural ingredients like herbs can and often do interact with prescription medications. At a minimum, we should have a complete list and look for obvious potential negative interactions (such as taking St. Johns wort with certain cholesterol medications, antidepressants or hormones), and also to promote further discussion.  For example, not only do WE not know everything contained in your supplement, YOU might not either.

This newly published JAMA study about Unapproved Pharmaceutical Ingredients  highlights our concerns. Cutting to the chase- some less reputable companies produce supplements that “WORK” because they include hidden ingredients that are actually prescription medications. In other words, if you look at the ingredient list, everything listed seems “natural” but when the pill/powder/capsule is chemically analyzed, voila- the manufacturer snuck in a drug not listed.

For example, the most common hidden ingredient in weight loss supplements is actually sibutramine, the generic name for the prescription drug MERIDIA. So what’s the problem? Isn’t this a great deal because now you can get the good drug for less money?  Well, NO. In fact, the FDA removed Meridia from the market because of concerns that the drug was increasing the risk of heart attacks and strokes. And obviously the supplement makers choosing to secretly include this drug are not going to slap cardiac warnings on their product, right? Also, Meridia is an SNRI (Seratonin and Norepinephrine Reuptake Inhibitor) which is a class of anti-depressant drugs, although this particular medication was used for its effect on decreasing appetite/facilitating weight loss. HOWEVER, if you happen to be taking an anti-anxiety or antidepressant medication that works in a similar fashion (such as SSRI’s like name brand Prozac, Zoloft, Paxil, Lexapro or other SNRI’s like Cymbalta or Effexor) and then you UNKNOWINGLY ADD IN Meridia, you are putting yourself at risk for serious interactions and side effects including a potentially fatal serotonin syndrome.

The other two highlighted supplement categories where “real” drugs are included are the “steroid-free” body building products (that contain synthetic steroids) and “natural” sexual enhancement products (that contain generic Viagra.) Again, YES, they WORK, but side effects, risks and drug interactions abound. College students- I’m talking to YOU-I see about one serious problem per month from these “natural” body building products.  

Supplements do not routinely fall under the scrutiny that prescription medications do because current FDA regulations consider them a food category. Technically these enzymes, vitamins, minerals and botanicals are not allowed to make medical claims about preventing, curing or treating certain conditions. Look closely, and you will see that every supplement has this disclaimer beautifully minimized and typically embedded within the back label, even when the front screams out promises of super-charged fat burning powers. Additionally, part of my mantra when talking about supplements is to emphasize that the lack of FDA product regulation means that the active ingredient dosing per pill tends to be less consistent, hence the reason so many of these supplements work better when prescribed several times per day (rather than once daily, where the variability of dose quantity would seem more obvious.)

Are ALL supplements BAD? Of course not! My last blog post included the potential benefits of peppermint oil (a supplement) in IBS. The vast majority of vitamin products- including those we prescribe such as B12 and Vitamin D- are good supplements (though quality varies by brand.) Certain pre- and probiotics, synthetic hormones like melatonin, and medicine herbs among others are all tools that can be beneficially incorporated into our practice of medicine, depending upon the individual patient, his or her medications, and medical conditions. HOWEVER, I will confess that I am a healthy skeptic of those that seem to work too well…especially the weight loss and body building ones. About a decade ago in my private practice, we started seeing a rash of patients with high blood pressure and chest pain that turned out to be caused by a popular weight loss product, which taught me to be more assertive when asking about “anything else?” How can you tell what’s safe? That’s a conversation for you, your doctor and your pharmacist, but please understand we have the most knowledge (and FDA control of ingredients) for prescription drugs.

BOTTOM LINE: ESPECIALLY if you take prescription medications, be aware that supplements have risks (just like other drugs) and please talk to your doctor before adding them to your regimen.






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