Dietary Supplement Concerns: Counsel, Don't Scold

Henry R. Black, MD; Rhonda Cooper-DeHoff, PharmD


October 05, 2015

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Henry R. Black, MD: Hi. I'm Dr Henry Black. I'm an adjunct professor of medicine at the Langone New York University (NYU) School of Medicine, and I'm here with my friend and colleague, Dr Cooper-DeHoff, from Florida. Thank you so much, Rhonda.

Rhonda Cooper-DeHoff, PharmD: Hi, and thank you for having me on this video conference. I'm an associate professor at the University of Florida, College of Pharmacy. I'm also the associate director for our pharmacogenomics center here in the College of Pharmacy.

Popularity and Cost of Dietary Supplements

Dr Black: At the American Society of Hypertension meeting in New York, you gave what I thought was a brilliant talk about dietary supplements[1]—so much so, that I wanted you to share it with the rest of us. Who uses dietary supplements?

Dr Cooper-DeHoff: Thank you for that compliment. What I would say about who uses them is, it's really everybody. If you look at the age range, you can see people from 18 years of age up to those in their 70s and 80s. It's females more than males and it's primarily wealthier people, because you have to be able to afford them, and it's also very ethnically diverse. So we see them used across multiple groups of people.

Dr Black: This must cost an enormous amount of money. What's the estimated amount of money spent on dietary supplements? And I should point out that we're not talking about vitamins necessarily but dietary supplements.

Dr Cooper-DeHoff: Right. We're talking about botanicals, and we're excluding vitamins and minerals from this conversation. It's estimated, based on 2012-2013 data,[2] that about $32 billion out-of-pocket is being spent on these products. That's a tremendous amount of money. About $10 billion is spent just on herbals, and that represents 33% of the entire out-of-pocket prescription medication expense during that time period. It's an enormous amount of money that we could imagine could be used in much more valued ways in regard to healthcare.

Dr Black: Why do you think these are so popular? Why are people using so many of them?

Dr Cooper-DeHoff: There are many influences on our patients, unfortunately, some of which come from the television. Without naming names, we have many high-level people who have television shows that expound on the virtues of these products when in fact there really aren't many. There isn't much of an evidence base to support their use. One of the biggest names was called to the carpet last year by the US Congress and Senate to explain the things he was saying, and he was told to stop.

Nevertheless, the problems continue. People look to these products—whether they're for weight loss, erectile dysfunction, or whatever—as a panacea because they don't want to see a doctor, they don't want to have to pay a copay. They can usually get the products over the Internet or easily at the local drug store, and they believe it will help cure an ailment, make them feel better, or give them more energy. That's what people want today.

Dr Black: Is this a placebo effect, do you think, or something more complex?

Dr Cooper-DeHoff: It depends. Many of these products have some effect. In some cases it can be a harmful effect, and in some ways it could be perceived as a good effect. What we're seeing today, especially in the past 3-5 years, is adulteration. The manufacturers of these supplements have caught on that people will keep buying them if there is some positive effect.

Areas of Concern

Dr Black: What do you think are the areas of major concern with dietary supplements? They're not regulated, they're marketed beyond description, and people seem to buy them in enormous quantities.

Dr Cooper-DeHoff: One of the reasons that people keep buying dietary supplements is that they do have some effect in some cases, and that's often because there are contaminants in them. For the erectile dysfunction supplements, manufacturers are starting to put sildenafil or tadalafil in them. That's obviously a concern, especially in our cardiac patients who might also be taking nitroglycerin or something like that. There could be a drug supplement interaction that no one might know about until the patient ends up dead in the bed.

There's also concern about pharmacokinetic or pharmacodynamic effects. An example might be a patient taking warfarin who also takes ginkgo biloba, for whatever reason, and they can have increased risk for bleeding. We know that thiazides and ginkgo biloba can result in increases in blood pressure, so that's kind of a pharmacodynamic mal-effect, if you will. There are a lot of things to be concerned about.

The US Food and Drug Administration is working hard to clamp down on these contaminated products, particularly in the weight loss area. Sibutramine, which was pulled off the market many, many years ago, is now routinely available in some of these supplements.[3] We've seen the new antiobesity drug lorcaserin found in supplements[4] that you can buy on the Internet. While the patient who takes that might have a beneficial effect, because of those adulterated pharmaceutical products they're opening themselves up to a lot of adverse effects. Their physician may not even know that they're exposed to that pharmaceutical compound.

What Can Healthcare Providers Do?

Dr Black: What advice do you give to healthcare provides about how they ought to deal with patients who take supplements? I guess the first thing is to ask them if they do and make sure that people list everything they take, whether they think it's a drug or not. What else do you recommend to healthcare providers?

Dr Cooper-DeHoff: I recommend having those conversations with your patients. I recommend adding a question about dietary supplements to the intake form that patients fill out while they're in the waiting room. I recommend having your nurse or your nurse practitioner ask the questions. We found that patients are often reluctant to talk to their physician about what they're taking but they might be more willing to talk to a nurse or a medical technician in the office. There are a lot of reasons for that: They feel that the physician might pooh-pooh what they're doing or just be very negative about it. They need to understand why there is concern and not just be told, "No, you can't do that,"—help them understand how to do it safely.

Dr Black: Do you think that patients are ashamed of doing this or do they just want to keep their doctor out of the loop?

Dr Cooper-DeHoff: I don't think it's about being ashamed. I think it's because they don't want to be told, "No, you can't do this." They would rather keep it a secret. I have a conversation with them: "If you're going to take these compounds, do it safely by going to reputable drug stores and looking for products that are USP [US Pharmacopeial Convention] verified."

The USP is an organization that regulates these products, on a voluntary basis, making sure that there are no contaminants or other adulterated compounds in them. Although the USP-verified products might be a little more expensive, I always gear my patients to look for those on the drugstore shelf and to stay away from anything on the Internet because it's completely unregulated.

Dr Black: I think that's the key advice. This is very important. This is a major part of our healthcare bill that people don't understand, and with your help I think more people will.

Dr Cooper-DeHoff: I think the most important thing is that we, as healthcare providers, need to have the expectation that our patients are taking these things. We need to help them let us know, and to do it safely.

Dr Black: Thank you very much for your time.

Dr Cooper-DeHoff: Thank you for inviting me to participate in this video conference.


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