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 and 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.