Many stimulants that are used for ADD and/or ADHD can cause a crashing effect on many, I know someone that as their meds wear off or he runs out, he can just curl in a ball and sleep for days, of course get up to eat and relieve himself, this also launches him into depression.
Due to him abusing his Ritalin, he is harming himself, triggering up and down cycling, but he is another story.
If you are feeling a change in mood while using your med, you should report it to your pdoc, it is important not to rollercoaster.
I wish you lots of luck with this, and always feel free to talk to us

Please take care,

DE