We have used Rosenthal's simplification of the tetrachlorphenolphthalein method of testing liver function1 in over 100 cases. In the majority of these patients, the diagnosis has ultimately been confirmed by operation, necropsy or unmistakable clinical course. On the whole, the test has not disappointed expectations, although sharp limitations have been found to its practical usefulness and a number of interesting problems have been encountered.
We have followed Rosenthal's technic except that in the course of the work we have slightly increased the dose of tetrachlorphenolphthalein used, first to 6 and then to 7 mg. per kilogram of body weight. We did this in the hope that the doubtful results, which were obtained with 5 mg. in cases in which it was fair to assume that slight liver injury existed, would show clear cut results with the larger amount of dye. Our work is sufficient to show that there is no