The 'AC' in Pepcid AC stands for 'Acid Controller', which makes sense since Pepcid AC is used to treat conditions caused by excess stomach acid, including heartburn, indigestion and GERD (gastroesophageal reflux disease).


Pepcid AC belongs to a family of medications known as H2 blockers. Other over the counter H2 blockers include:

  • Zantac (ranitidine)
  • Tagamet (cimetidine)


H2 blockers work via two mechanism:

  • Decrease the amount of stomach acid produced.
  • Reduce our bodies acid producing response to certain stimuli, like food.


All over the counter H2 blockers have similar effectiveness but Pepcid AC is thought to have significantly fewer potential drug interactions than Tagamet.