Side Effects of Adderall

I'm a non-ADHD spouse, and my husband started taking 10mg of Adderall about 2 weeks ago. XR during day and IR when that wears off late afternoon. First medication ever, age 52. It is a dramatic difference and we are both relieved and happy with the results so far. Yesterday, however, he felt really unwell and didn't feel "right." We notice that he is forgetting to eat all day/not hungry, is bad about drinking enough water, and last night his daughter didn't sleep well so he was up most of the night. 

Could the lack of sleep plus lack of food cause him to feel more "off" than the average non-ADHD, unmediated person?  It scared him so he stopped taking the adderall and of course he's right back to severe ADHD symptoms. 

What is your experience, or what may have you heard or learned?

thank you!