Pulling back sensation?

[ironmics]

So swim has been taking pain killers for awhile now, and has posted quite a few times about tramadol. Well last night he took 100mg as prescribed when he has bad pain. If he sat and looked at one thing for awhile his depth perception felt so weird and he felt like he was being pull back from the world. He was having a pretty serious discussion at the time so thought it might just be anxiety of something. But sure enough 100mg again tonight and he's pulling away from his computer. Rather an odd feeling, but not bad by any means. Does this happen to anyone else on any other opiates?