A new RP-HPLC method was developed for the determination of cardenolid
es in Convallaria majalis. Hypersil ODS 3 mu m as stationary and aceto
nitrile/water (88 + 12) as mobile phase and gradient elution were used
for the separation. For the quantification of the total and single am
ounts of the cardenolides helveticoside was added as internal standard
. The reproducibility and accuracy of the method as well as the natura
l variability of the cardenolide complex in Herba Convallariae were de
termined by analysis of 13 samples of C.