Rite aid antacid effervescent tablets provide fast of: acid indigestion, upset stomach, heartburn with headache, body aches and pains. Original flavor; Effervescent tablets; Anhydrous citric acid/antacid; Fast of acid indigestion, upset stomach, heartburn with headache, body aches and pains; Compare to the active ingredients in alka-seltzer; This item may be eligible for FSA and HSA reimbursement.