Two models of the aconitin-induced cardiac arrhythmias were used to compare the antiarrhythmic and antifibrillatory activity of the reference drug Lappaconitine hydrobromide and the LMG-124 compound. It is shown that both compounds have antiarrhythmic action. At the same time, the compound LMG-124 realizes its antiarrhythmic effect in a significantly lower dose. In this case, the compound LMG-124 shows a pronounced antifibrillatory activity, in contrast to the reference drug Lappaconitine hydrobromide, which in the studied dose does not exhibit similar activity.

A method for the quantitative determination of the reference sample of lappaconitine by HPLC has been developed and included in the project of normative documentation for this drug. The proposed analytical technique is completely validated, including the entire complex of characteristics for the specificity, suitability of the chromatographic system, and the linearity, repeatability, and reproducibility of HPLC analyses.