Volume 37, Issue 2, 1 February 2015, Pages 275–301
Review Article
Multi-ingredient, Caffeine-containing Dietary Supplements: History, Safety, and Efficacy
Abstract
Purpose
Our
objective was to review the history, safety, and efficacy of
caffeine-containing dietary supplements in the United States and Canada.
Methods
PubMed
and Web of Science databases (1980-2014) were searched for articles
related to the pharmacology, toxicology, and efficacy of
caffeine-containing dietary supplements with an emphasis on Ephedra-containing supplements, Ephedra-free supplements, and energy drinks or shots.
Findings
Among the first and most successful dietary supplements to be marketed in the United States were those containing Ephedra—combinations
of ephedrine alkaloids, caffeine, and other phytochemicals. A decade
after their inception, serious tolerability concerns prompted removal of
Ephedra supplements from the US and Canadian markets. Ephedra-free products, however, quickly filled this void. Ephedra-free
supplements typically contain multiple caffeine sources in conjunction
with other botanical extracts whose purposes can often be puzzling and
their pharmacologic properties difficult to predict. Ingestion of these
products in the form of tablets, capsules, or other solid dosage forms
as weight loss aids, exercise performance enhancers, or energy boosters
have once again brought their tolerability and efficacy into question.
In addition to Ephedra-free solid dosage forms,
caffeine-containing energy drinks have gained a foothold in the world
market along with concerns about their tolerability.
Implications
This
review addresses some of the pharmacologic and pharmaceutical issues
that distinguish caffeine-containing dietary supplement formulations
from traditional caffeine-containing beverages. Such distinctions may
account for the increasing tolerability concerns affiliated with these
products.
Key words
- caffeine;
- dietary supplements;
- Ephedra;
- Ephedra-free;
- energy drinks
Copyright © 2015 Elsevier HS Journals, Inc. All rights reserved.
