Fran Lowry

April 03, 2014

Pharmacists are the ideal people to inform patients about the correct and incorrect use of dietary supplements, which are increasingly being used and can be harmful, especially if a person has a chronic health condition, according to information presented at the American Pharmacists Association 2014 Annual Meeting and Exposition in Orlando, Florida.

"Whether you know about it or not, many of your patients are using dietary supplements to manage chronic conditions," said Bella Mehta, PharmD, from The Ohio State University in Columbus.

"It is important for us, as pharmacists, to be aware of the evidence-based processes behind some of the most popularly used natural products," she told Medscape Medical News.

"Pharmacists already know that 'natural' does not necessarily mean safe. But they should remember to look at drug interactions and the side effects that can occur from some commonly used products. They also should have resources on what products are reliable and safe for patients," Dr. Mehta explained.

Just Ask

Copresenter Kelly Orr, PharmD, from the University of Rhode Island in Kingston, noted that patients are using dietary supplements whether the pharmacist knows it or not.

"It's important to ask everyone about their supplement use and the reasons they chose a particular product," Dr. Orr told Medscape Medical News.

She added that counseling patients not to take a natural product because it is not approved by the US Food and Drug Administration (FDA) often conveys a sense that pharmacists, as health professionals, are biased, and some patients will continue to use it despite the advice.

"Providing detailed information regarding the known efficacy and the safety concerns about a product will help bridge that communication gap, resulting in safer self-care decisions for our patients," Dr. Orr said.

All pharmacists, whether they work in hospital settings or in the community, should ask patients about the products they are using.

"Just inquire. Are you using any dietary supplements? If so, what are you using, or what are you thinking about using? This way, you can look at the whole profile. You will have a list of the patient's medications and you can proactively screen for potential problems," Dr. Mehta said.

In their talk, Dr. Mehta discussed popular products for diabetes and osteoporosis, and Dr. Orr discussed those used for migraine headaches and insomnia.


In 2003, it was reported that cinnamon, specifically cassia cinnamon, has a significant positive effect on blood glucose and cholesterol (Diabetes Care. 2003;26:3215-3218).

"You will find a lot of physicians recommending cinnamon and a lot of patients taking it. Even though larger studies didn't show benefit, when you look at the benefit-to-risk ratio with cassia cinnamon, it's positive," Dr. Mehta explained. "Because there is very little harm but a potential benefit, we would recommend it."

However, there have been isolated reports of hepatotoxicity with cinnamon when taken in large doses.


For butterbur, a plant in the ragweed family, the established evidence for the prevention of migraine is level A, according to the American Academy of Neurology and the American Headache Society.

However, "this is a product that is not usually stocked," and is difficult to find in community pharmacies, Dr. Orr noted. When selecting a butterbur product, be sure it is clearly labeled as free of pyrrolizidine alkaloids, which are potentially hepatotoxic.

Although level A evidence for the prevention of migraine headaches is strong, long-term data, beyond 12 to 16 weeks, on the use of butterbur are lacking, she explained. In addition, because butterbur is in the same family as ragweed, allergic reactions can occur.


For osteoarthritis, there are a number of different products, but the ones that get the most attention are glucosamine and chondroitin, Dr. Mehta said.

Early studies on the effectiveness of glucosamine and chondroitin in osteoarthritis compared glucosamine sulfate with either placebo or nonsteroidal anti-inflammatory drugs (NSAIDs). Those studies found that for mild osteoarthritis, glucosamine sulfate appeared to be beneficial.

However, more recent studies looking at moderate to severe osteoarthritis are finding that the combination of glucosamine hydrochloride and chondroitin sulfate might be more beneficial, she said.

The problem is that the consumer has to be quite savvy to know whether their osteoarthritis is classified as mild or as moderate to severe to get the most benefit, she noted.

"We think that these compounds work in the same pathways as the nonsteroidal and COX-2 inhibitors, so the idea is that they are working in the COX-1 and COX-2 pathways," Dr. Mehta explained.

If shellfish is used as the source for glucosamine and chondroitin, there can be a problem because of shellfish allergies, she noted. But most of the newer products are come from other sources. In addition, blood thinners, such as warfarin, can interact with glucosamine and chondroitin supplements.


The supplement getting the most attention right now is melatonin, Dr. Orr said.

"We have typically thought of it for jet lag, but it is often used for insomnia, especially in children," she said.

Melatonin has orphan drug status and is approved for the treatment of both non-24 hour sleep/wake disorders and circadian sleep disorders in people who are totally blind, including children, Dr. Orr explained.

"It helps to push the circadian rhythm and appears to help sleep onset. The newest studies are looking at preschool toddler-aged children and children with attention deficit disorder to see if it helps shorten the time it takes them to fall asleep. Most of the studies have been small and of short duration, but melatonin has shown some benefit," she said.

Melatonin is produced naturally in the body by the pineal gland, and it might be that these children and adults are not producing the right amount. Use in children and especially adolescents is controversial because of the unknown hormonal effects, she added.

Melatonin can interact with a number of drugs, such as tricyclic antidepressants, monoamine oxidase inhibitors, benzodiazepines, and calcium-channel blockers. "It is very important to make sure that melatonin interaction is not an issue," Dr. Orr noted. "Patients who decide to take melatonin for their jet lag should be aware of these interactions."

Resources for Pharmacists

There are reliable sources for pharmacists who offer these and other dietary supplements to their patients.

These include, the US Pharmacopeial Convention Verification Services, the Natural Products Association (formerly the National Nutritional Foods Association), and NSF International, Dr. Orr said.

In addition, "products are often recalled on the FDA Web site during postmarketing surveillance. It is helpful to select products that have a quality seal or are produced from a reputable manufacturer," she said.

The information presented by Dr. Mehta and Dr. Orr about these common dietary supplements is very useful, said Sarah Lorentz, PharmD, from the UCSD Skaggs School of Pharmacy and Pharmaceutical Sciences in La Jolla, California.

"Their talk was very evidence-based and had helpful information for those of us who have patients who want to use these products," Dr. Lorentz told Medscape Medical News.

Dr. Mehta, Dr. Orr, and Dr. Lorentz have disclosed no relevant financial relationships.

American Pharmacists Association (APhA) 2014 Annual Meeting and Exposition. Presented March 30, 2014.


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