PPI's like Nexium, Prilosec and Aciphex are OK to take with the riba, as are OTC H-2 pumps like Zantac
AC. Pepsid Complete, on the other hand, contains an antacid, so it should also be spaced away from the riba. Same with Gaviscon -- space it away from the riba.
Also, if you want to be somewhat riba neurotic as I unabashedly was , don't take the riba with flax, metamucil, bran or other fiber supplementation, as in theory it will also impede riba absorption.