The best replacement for pepto is tums.

The best alternatives to pepto are rated as following:
★★★★★  tums
★★★★  imodium
★★★  maalox
★★  mylanta
★★  kaopectate
★  pepcid
★  immodium
★  milk of magnesia
★  gas x
★  alka seltzer

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

Other search terms related to pepto and their ratings are:

★★★★★ imodium
You have in mind a companion for pepto and it is not yet here? Propose!

Google Trends

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