I'm 18 and I get Remicade usually first thing in the morning so I can sleep the whole day and be somewhat alert the next day. The fatigue does remain for a few days for me, but I'm usually fine and feeling good after the first week after I get my infusion. I'd say probably wait it out and make sure he gets lots of rest. Since he's new to the Remicade though, it can take awhile to kick in, mine took 2 or 3 months before I was finally feeling good. Im going through a flare and my body has started to reject the remicade, so I'm tired all the time and know how he feels. I hope he starts feeling well again soon!