To user 934576,
One might be able to do either, but I take one with my breakfast and one with my supper. I don't recall back when I first started taking them if they worked the first night or if I had to take them a short while before feeling the results as is often the case with many supplements. Anyway, they've worked for me for many years, and if I think I no longer need them, I soon receive a rude and painful reminder!
Best wishes.