These five drugs are interesting since they affect the various tissues differently. A.T.S. acid is very toxic to all the tissues grown in vitro.
From our experiments it is clear that carbarsone is not very injurious to the tissues of the digestive tract, though the epithelium is sometimes affected. These findings are in agreement with those of Leake (6) who speaks of “its superiority to any amoebicide in ordinary use.”
Kurchi bismuth iodide in low dilutions kills all the tissue culture cells. In higher dilutions it is injurious to the fibroblasts but does not affect the epithelium.
Proparsamide is very injurious to sympathetic nerves and has little effect on the other tissues.
Vioform has been found to be excellent for the treatment of amoebiasis in monkeys (Anderson and Koch (7)). Since the epithelial tissue culture cells can live in its higher dilutions, it may prove a useful drug though it is very toxic to fibroblasts in all the dilutions used.
Of the three arsenic compounds, carbarsone, with the highest arsenic content (28.85 per cent) and a valence of five, is the least injurious to the tissue culture cells. Proparsamide with its 26 per cent arsenic content and a valence of five affects only the nerves, while A.T.S. with the lowest arsenic content (13 per cent) and a valence of three is the most injurious to all the cells.