What causes red bumps after leg waxing?

What causes red bumps after leg waxing?
The condition you describe is folliculitus - an infection of the hair follicles. Damage to the hair follicle, from waxing, shaving, excessive heat, can lead to this condition. Try bacitracin 3x/day for 10 days and thereafter aquaphor 2x/day until scarring fades. Or do to your dermatologist if infection persists (ie. bumps ooze out pus). Stop the waxing for now until you get it checked out.
allergic reactions
Probably irritation from the razor.