@dbamos1945 Even though I have taken Fosamax, I don't know about Pepsid OTC as I have not taken any antiacid medications. You likely already saw this AI comment: Yes, taking Pepcid AC (famotidine) can decrease the absorption of Fosamax (alendronate) if they are taken at the same time.To maximize the absorption of Fosamax, health experts recommend following these steps:Wait 30 Minutes: You should wait at least 30 minutes after taking your Fosamax before taking Pepcid AC or any other acid-reducing medication.Follow strict fasting rules: Fosamax must be taken first thing in the morning with a full glass of plain water, at least 30 minutes before your first food, drink (other than water), or other medications.