nothing is objectively cool, outside of fonzie. assuming he's not on medication, i don't see why it should be a problem, but there's really only the one way to find out for sure.
Probably best to research what medications he is currently taking, and the MOA of said drugs to see if LSD might potentially interact with them. I would start there if I were you... I think he would be fine, but as the saying goes; Better safe than sorry.
