Alkalinizing agent / histamine-2 antagonist combinations are used to treat heartburn, gastroesophageal reflux disease (GERD), and indigestion. These medications work by combining an alkalinizing agent, which neutralizes stomach acid, with a histamine-2 antagonist, which reduces the amount of acid your stomach produces. These combinations are typically available in oral forms, such as chewable tablets. An example includes famotidine complete (Pepcid Complete). You can take these medications to help manage your condition.