The best replacement for heartgard is heartgard plus.

The best alternatives to heartgard are rated as following:
★★★★★  heartgard plus
★★★★★  interceptor
★★★★  sentinel
★★★  iverhart
★★★  revolution
★  trifexis
  interceptor dogs
  heart shield
  nuheart
  quadriguard
  wormshield
  tri heart plus
  advantage multi
  proheart

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

Other search terms related to heartgard and their ratings are:
★★★★★ heartworms
★★★★ comfortis
You have in mind a companion for heartgard and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of heartgard in all years. Click on graph for more.
heartgard
heartgard plus
interceptor