I noticed that the scopolamine patches are most effective in the first couple of hours after applying them. They last for three days, but their antidepressant effect only lasts a day for me (maybe not even a day). I suspect that the brain reacts to the scopolamine and attempts to restore the previous equilibrium (which was depression unfortunately). So the patches keep delivering the scopolamine to sustain a certain concentration in my body, but the body learns to counteract the scopolamine and bring me back to my usual state of depression. I have also read that the patches deliver a fast dose at the beginning to load the person's body with scopolamine, but then they deliver a slow dose to sustain that concentration of scopolamine.