I think that while possible, ADHD medication shouldn't cause a worsening of mental health symptoms (I'm not sure if the dark spiral you mention is depression?). Like the above poster said, you should definitely talk to your pdoc about this. It might just be that this isn't the medication for your - there are other meds to treat ADHD if you decide you want to continue taking medication. It takes some time to figure out which one is the best and what dosage is the most effective.