The best replacement for fainting is seizure.

The best alternatives to fainting are rated as following:
★★★★★  seizure
★★★★  passing out
★★  blacking out
★★  syncope
★  panic attack
★  blackouts
★  dizziness
★  blackout
★  fitting
★  seizures
★  mini stroke
★  epilepsy
  sleeping
  anaphylaxis
  collapsing
  falling asleep
  fainting
  pass out

Your alternative for fainting is not listed? Suggest!
Speaking about fainting, one probably shouldn't forget about seizure.

Other search terms related to fainting and their ratings are:
★★★★★ seizure
★★ convulsions
★ blacking out
★ dizziness
★ loss of consciousness
loss of bladder control
You have in mind a companion for fainting and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of fainting in all years. Click on graph for more.
fainting
seizure
passing out