Electrocardiographic and blood pressure effects of the ephedra-containing TrimSpa thermogenic herbal compound in healthy volunteers.

STUDY OBJECTIVE: To determine the effect of an ephedra-containing thermogenic herbal compound (TrimSpa) on rate-corrected QT (QTc) interval duration and systolic blood pressure. DESIGN: Randomized, double-blind, placebo-controlled, crossover, intent-to-treat study. SETTING: Student laboratory at a college of pharmacy. SUBJECTS: Thirteen healthy volunteers (eight men, five women). INTERVENTION: Participants were given TrimSpa, which contains more than 30 ingredients including ephedra 15 mg and caffeine 60 mg, or matching placebo 3 times/day for 7 days in a crossover fashion with a 7-day washout period between treatments. MEASUREMENTS AND MAIN RESULTS: Each subject's QTc interval and systolic blood pressure were measured on days 1, 4, and 7. These measurements were performed immediately before study drug ingestion (baseline) and 0.5, 1, and 3 hours after ingestion. No differences in these variables were found between the TrimSpa and placebo groups. In one subject taking TrimSpa, the QTc interval increased 96 msec from baseline, more than double the largest increase in the placebo group. CONCLUSION: Standard doses of TrimSpa did not induce changes in subjects' QTc intervals or systolic blood pressures. However, because the QTc interval dramatically changed in one subject taking TrimSpa, a large study is needed to determine if the effect is an artifact or if the subject represents a subset of people for whom the drug may pose a risk.

Electrocardiographic and hemodynamic effects of Panax ginseng.

OBJECTIVE: To determine whether Panax ginseng ingestion can acutely or chronically alter electrocardiographic parameters: PR, QRS, QT, QTc, and RR intervals, and QT and QTc interval dispersion. Effects of P. ginseng on blood pressure and heart rate also were evaluated. METHODS: This is a prospective, randomized, double-blind, placebo-controlled study of healthy adults at the University of Connecticut. Thirty subjects were randomly allocated to receive 28 days of therapy with either P. ginseng extract 200 mg or placebo. Baseline 12-lead electrocardiograms (ECGs) were obtained. Subsequent ECGs were performed following study drug ingestion at 50 minutes, 2 hours, and 5 hours on days 1 and 28. Blood pressure readings were taken with each ECG. RESULTS: P. ginseng ingestion increased the QTc interval by 0.015 seconds on day 1 at 2 hours compared with the placebo group (p = 0.03). It also reduced diastolic blood pressure from 75 +/- 5 mm Hg at baseline to 70 +/- 6 mm Hg at the same time point (p = 0.02). The observed effects are not believed to be clinically significant. No other statistically significant changes were found in electrocardiographic or hemodynamic variables on days 1 or 28. CONCLUSIONS: P. ginseng, at doses of 200 mg of the extract daily, increases the QTc interval and decreases diastolic blood pressure 2 hours after ingestion in healthy adults on the first day of therapy.