TUMS Extra Strength Antacid Tablets go to work in seconds by starting to neutralize acid on contact to bring fast and powerful extra-strength heartburn relief. When symptoms occur, chew and swallow two to four tablets, depending on the severity of your acid indigestion. Featuring the active ingredient calcium carbonate, these berry-flavored chewable antacid tablets relieve heartburn, sour stomach, acid indigestion and provide upset stomach relief associated with these symptoms. TUMS antacids are the #1 recommended adult antacid brand by doctors, pharmacists, and OBGYNs. It is America's #1 antacid, trusted as a heartburn medicine for 90 years, fully supported with a satisfaction guarantee. These chewable antacids are gluten free and kosher. Packaged in a compact, resealable bottle perfect for keeping in your car or office, TUMS Extra Strength Assorted Berries antacids fight flare ups fast.