What is the interaction between methylphenidate (Ritalin, Concerta, Metadate, Methylin) and calcium carbonate (Tums, Tums Ultra)? I recently read that the calcium carbonate increased methylphenidates affects. If so, in what way. I have hypertension, but take a very low does (18mg/day)of Concerta each day. I just need to know if the Tums might create an additional hypertensive or stimulant effect. If so, I guess I'll find something else for my heart burn. Can you help le?!