When heartburn starts, stop it fast with Alka-Seltzer Heartburn Relief. Alka-Seltzer speeds its unique effervescent formula to where it*s needed-fast.Try Alka-Seltzer® Heartburn Relief to extinguish the fire of your worst heartburn fast. Its unique effervescent formula starts to work the instant you take it. It*s faster than Pepcid AC®, Zantac® and even the leading prescription and is available in a cool effervescent lemon-lime flavor Cool Lemon-Lime taste Uses for the relief of:heartburn acid indigestion upset stomach associated with these symptoms