With the purpose to study the therapeutic effects of the derivatives of alkyldisulfide form-B(1) on the fall in the pulse beats, the author performed experiments with albino rats by administering TTFD and pursued the recovery of the fall in the pulse beats and compared these results with the effects of B1 and TPD. Forty albino rats weighing about 60g each were fed on the regular diet for two weeks and they were given a vitamin-B(1) deficient food. Then selecting those showing B(1)-deficiency and having the pulse beats of about 300/min, these were divided into three gruops of each given a subcutaneous injection of B(1), TPD, or TTFD in the dose equivalent to 5γ B(1), and the changes in their pulse beat were estimaed along with the lapse of time by electrocardiogram. As the results all the three groups showed the favorable effect on the low pulse beats. Namely, the rate of rise in the pulse beat was more rapid in TPD and TTFD groups rather in that of B(1) group. The maximum increase in the pulse beat in the B(1)-group was superior to TPD group, whill the maximum in TTFD group was inferior to the other two groups. The duration of therapeutic effect was longest with TPD followed by B(1) and shortest with TTFD.