Page 1145 - Basic _ Clinical Pharmacology ( PDFDrive )

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Dietary Supplements &

Herbal Medications *

Cathi E. Dennehy, PharmD, &
Candy Tsourounis, PharmD

C ASE STUD Y

A 53-year-old woman with a history of knee osteoarthritis, is high at 160/100 mm Hg. Her prescription medications
high cholesterol, type 2 diabetes, and hypertension presents include simvastatin, metformin, and benazepril. She also
with new onset of hot flashes and a question about a dietary takes over-the-counter ibuprofen for occasional knee pain
supplement. She is obese (body mass index [BMI] 33), does and a multivitamin supplement once daily. She has heard
not exercise, and spends a good portion of her work day in a good things about natural products and asks you if taking a
seated position. She eats a low-sugar diet and regularly eats garlic supplement daily could help to bring her blood pres-
packaged frozen meals for dinner because she doesn’t have sure and cholesterol under control. She’s also very interested
time to cook regularly. Her most recent laboratory values in St. John’s wort after a friend told her that it helped allevi-
include a low-density lipoprotein (LDL) cholesterol that is ate her hot flashes and could also help improve mood. How
above goal at 160 mg/dL (goal < 100 mg/dL) and a hemo- should you advise her? Are there any supplements that could
globin A that is well controlled at 6%. Her blood pressure increase bleeding risk if taken with ibuprofen?
1c

The medical use of plants in their natural and unprocessed form multidisciplinary, collaborative review committee of experts.
undoubtedly began when the first intelligent animals noticed that The recommendations in this database are limited by the quality
certain food plants altered particular body functions. While there of the existing research and the quality of the dietary supple-
is a great deal of historical information about the use of plant- ment used at the time of the report. As a result, all statements
based supplements, there is also much unreliable information as a regarding positive benefits should be regarded as preliminary,
result of unknown or poor-quality natural product formulations, and conclusions regarding safety should be considered tentative
poorly designed clinical studies that do not account for random- at this time.
ization errors, confounders, and—most importantly—a placebo For legal purposes, “dietary supplements” are distinguished
effect that can contribute 30–50% of the observed response. Since from “prescription drugs” derived from plants (morphine, digi-
the literature surrounding dietary supplements is evolving, repu- talis, atropine, etc) by virtue of being available without a pre-
table evidence-based resources should be used to evaluate claims scription and, unlike “over-the-counter medications,” are legally
and guide treatment decisions. An unbiased and regularly updated considered dietary supplements rather than drugs. This distinc-
compendium of basic and clinical information regarding botani- tion eliminates the need for proof of efficacy and safety prior
cals is Natural Medicines by Therapeutic Research Center (see to marketing and also places the burden of proof on the FDA
References), which includes content review by an international, to prove that a supplement is harmful before it can be removed
from the market or its use can be restricted. Furthermore,
* The US Food and Drug Administration (FDA) recognizes “herbal marketed dietary supplements are not tested for dose-response
medication” and “botanical medication” as “dietary supplements.” For relationships or toxicity, and there is a lack of adequate testing
the purposes of this chapter, they are identical.
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