How do you guys cope with the end of day Dex come down?

Dex has been amazing for me. Overall productivity has gone up heaps. It doesn't really make me feel any different except for just being overall more able to get things done.

Big draw back though. Massive mood dip at the end of the day. I feel irritable and just uncomfortable, just a general negative state. I can't take any past 4pm or I won't sleep.

Has anyone found a way to manage this? Is it even happening to others?