The best replacement for harm is hurt.

The best alternatives to harm are rated as following:
★★★★★  hurt
★★★★  damage
★★  injury
★★  loss
★★  hype
★★  dependence
★  injure
★  alarm
★  indirect harm
★  hazard
  suicide
  benefit
  danger
  crime
  self injury
  number needed to treat
  my own worst enemy
  do good
  diffuse magic
  addiction

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

Other search terms related to harm and their ratings are:
★★★★★ intent
★★ cutting
needles
You have in mind a companion for harm and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of harm in all years. Click on graph for more.
harm
hurt
damage