"Through the Lightning Gate" by Jim Eldridge could be possibility:
Synopsis from the back cover:
Meet Freddy A. Kennedy - alias Freak. He's seventeen and pretty cool
with it - but nothing could have prepared him for being zapped through
the lighting gate... into a world where tribes of lizard-creatures and
snarling dog-people prowl the streets night and day.
Enter Eon, the lion woman. She's the only one Freak meets who doesn't
try to tear him limb from limb - she even helps him understand what's
going on. So when Eon disappears, captured by the evil warlord Angel,
Freak plans a rescue mission.