My pcp and my GI dr both have said that taking things like tums, rolaids is perfectly fine with PPIs, which are proton pump inhibitors, which is what omeprazole is. I've read on here that a lot of the posters take gaviscon (sp?) it's the liquid anti-heartburn that also sooths the esophagus as it goes down. Now as far as the OTC Zantac, which are different than Tums... I know several reflux sufferers that take that as well as their PPI, but I'd say only with Dr recommendation. But as far as Tums and the like, it's fine.
Are you taking the OTC? I took that a long time, but eventually the 20mg 1x a day dose wasn't doing anything for my reflux. I read somewhere that the OTC omeprazole isn't ideal for long term use, I think and could be wrong on this please someone correct me if I am, it's because of what the medicine is made with (possibly mercury but can't remember really) versus the prescription strength which is more ideal for long term use... but of course that requires trip to you dr and authorization by your insurance. If you continue to suffer more than a few weeks I'd at least see your primary care dr.