Original Alka-Seltzer antacid and pain relief medicine. Each effervescent tablet contains 325mg aspirin (NSAID), 1000mg anhydrous citric acid, and 1916mg sodium bicarbonate (NSAID). Alka-Seltzer tablets provide fast relief of heartburn, acid indigestion, sour stomach with headache, body aches and pain. Workplace dispenser box of Alka-Seltzer contains 72 individually wrapped effervescent tablets. Fizzy relief so you can just get on with it.