Historical clue formulations

• Tummy soother — 2020-12-01
• Upset stomach soother, informally — 2020-01-21
• Stomach settler — 2014-08-24
• Leavening agent, briefly — 2012-08-03
• Internal settler? — 2009-09-06
• Acid reducer, briefly — 2005-03-19
• NaHCO3 — 2000-09-30
• Stomachache reliever, familiarly — 1998-11-08