Evaluation of the stimulant content of dietary supplements marketed as "ephedra-free".

Background: With the removal of stimulant herb ephedra from the market, dietary supplement manufacturers are coming out with many ephedra-free products. Some of these products appear to simply replace ephedra with stimulants by another name.

Objective: To determine the stimulant content of dietary supplements marketed as ephedra-free.

Design: Survey of the ingredients of dietary supplements that are stated as "ephedra-free" in the label or promotional material.

Results: Out of 36 products marketed as ephedra-free, 32 (89%) contained a methylxanthine such as caffeine or theobromine, 21 (58%) contained the stimulant synephrine, and 20 (56%) contained both a methylxanthine and synephrine.

Limitations: The results of this evaluation pertain only to products discovered through Internet and database searching.

Conclusions: Most dietary supplement makers have substituted stimulants by a different name for ephedra in their "ephedra-free" products. Patients need to be advised that ephedra-free products are not necessarily stimulant free and may present a significant risk.