Antacids (Tums, Maalox, Mylanta) and Famciclovir interaction
Antacids (Tums, Maalox, Mylanta) and Famciclovir: the Famciclovir prescribing label reports no clinically significant interaction between these two.
No clinically significant interaction reported. The label studied or considered this pair and found nothing meaningful.
What the FDA labels say
From the Famciclovir label · effective 2026-01-14
…Penciclovir No clinically significant alterations in penciclovir pharmacokinetics were observed following single-dose administration of 500 mg famciclovir after pretreatment with multiple doses of allopurinol, cimetidine, theophylline, zidovudine, promethazine, when given shortly after an antacid (magnesium and aluminum hydroxide), or concomitantly with emtricitabine.
Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.
Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.