It has been my intention for some time past to discuss the literature of strophanthin exhaustively. I have not yet been able to perform this task, but certain conditions have arisen which, unless counteracted by a word of warning, will entail accidents, thereby bringing this drug into disrepute at the very time when it gives the greatest promise of usefulness.
I have stated1 that the tincture of strophanthus generally sold in the United States is of fairly uniform potency, and that the strophanthin of Merck and that of Boehringer and Sons are of practically the same activity, being about half as active as the crystalline ouabain, or so-called crystalline strophanthin of Thoms made by Merck.2
We have examined many specimens of strophanthus seed and tincture of strophanthus in the laboratory of the Department of Pharmacology and Materia Medica of Cornell University Medical College
HATCHER RA. NOTE ON STROPHANTHIN. JAMA. 1910;LIV(13):1050–1051. doi:10.1001/jama.1910.92550390004002j