We disagree with the comments of Drs. Kingston and Borron, Dr. Whitaker, and Dr. Dickinson. The data from the national system of Poison Control Centers provide a critical safety valve for consumers. Health researchers, government agencies, and product manufacturers rely on these data to warn the public about product dangers and to design safer products.

Drs. Kingston and Borron note that, on average, 15.4% of adverse event reports that the Poison Control Centers receive are later judged to be unrelated to the herb under examination. If 15.4% of adverse event reports are removed from each of the herbs in our data set, then the relative risks we calculated remain exactly the same. In the extreme case, even if 15.4% of ephedra cases are judged to be unrelated versus 0% of cases reported for all other herbs, the relative risk for an adverse event with ephedra compared with all other herbs decreases only from 40 to 34 (95% CI, 31 to 38).

We agree with Dr. Whitaker's assessment that ephedra is a drug and a known stimulant (the pharmacologic basis for most of its adverse effects). While it would be interesting to compare the frequency of adverse events from ephedra with those from other sympathomimetic stimulants (for example, cocaine and amphetamines), we believe it is more important to distinguish the safety of ephedra from that of other herbal products. We found that ephedra had an enormous increased relative risk of 40, or a 3900% increase in risk, compared with other commonly used herbs, both individually and combined, which strongly supports the conclusion that ephedra use is unsafe.

We are perplexed at Dr. Dickinson's statistic of ephedra sales from the Nutrition Business Journal. We did not rely on this journal's data because the journal uses an unspecified combination of sales data and information from surveys of herbal manufacturers (1) and also uses dollar sales rather than unit sales (the relatively expensive cost of ephedra products biases the dollar sales estimates).

We stand by our conclusions that ephedra supplements pose a disproportionate health risk and that their use should be restricted (2). Our findings are in agreement with the RAND Corporation's analysis of case reports, which suggests a link between ephedra products and such catastrophic events as sudden death, heart attack, stroke, seizures, and serious psychiatric symptoms (3).