I took it for about 1 month, some weeks I took 2-3 pills and some days I took 10 pills, I didn't research enough to know if vitamin b1 has a cumulative effect or taking it for 1 month differs from taking it for the first time, so I didn't have consistency in always taking the same dose for a sequence of days correctly or every week correctly, but I already took several dosages and nothing changed for me except a small placebo that soon disappeared.