Ephedra-containing dietary supplements are consumed to improve sports performace, but may carry risks of cardiac and neurological adverse events. Little is known of their use by young athletes. Our aim was to determine the prevalence and patterns of ephedra use among high school athletes. An anonymous survey was performed in Rochester, Minnesota on high school athletes who participated in fall sports during 2003-04. Parental consent was obtained for athletes under age 18 years. Surveys were distributed at preparticipation examinations and in- school survey stations. The response rate to the survey was 68.2%, or 311 respondents out of a possible 456 with consent (or 26% of all 1197 athletes eligible prior to the consent process). Seven of 311 (2.3%) respondents used dietary supplements containing ephedra. Only one of seven users (14.3%) knew that the supplements they used contained ephedra. Ephedra use was more common in boys (five) than girls (two). Ephedra use was only found in 17 and 18-year-olds. The most common sports among ephedra users were football, track and field, and weightlifting. This study suggests that Ephedra use was infrequent among the young athletes in this population. However, ephedra users were generally unaware that the dietary supplements they consumed contained ephedra. Users were more likely to participate in football, track and field, and weightlifting. Ephedra users were likely to obtain supplements from their peers, and were largely uninformed of the content of their supplements.