In this 2 x 2, randomized, crossover bioequivalence study, two tablet preparations of helicidum were compared in 20 healthy Chinese male subjects. The drug was given in a single dose of three tablets (75 mg) and blood samples were withdrawn during 12 h after drug administration. Helicidum was separated and analyzed using a validated liquid chromatography-mass spectrum method. The pharmacokinetic parameters were determined from the plasma concentration-time profiles of both formulations. The primary calculated pharmacokinetic parameters were compared statistically to evaluate bioequivalence between the two preparations, using various statistical methods. The analysis of variance (ANOVA) did not show any significant difference between the two formulations and 90% confidence intervals fell within the acceptable range (80-120%) for bioequivalence. Based on these statistical inferences it can be concluded that the two tablet preparations of helicidum are likely to be bioequivalent.