There are LOTS of other options. Nexium is significantly stronger than Prilosec but is similar chemically to Prilosec.
There are a nuraber of other proton pump inhibitor medications: Aciphex, Protonix, Kapidex, Prevacid (just to name a few).
Everyone responRAB differently to medications so you need to have a discussion with your doctor, explain that the Prilosec isn't working well, and ask the doctor to prescribe something else until you find one that works for you.
It's also important to make the necessary lifestyle changes to help minimize reflux - the medications won't solve the problem, they just help keep it in check - but there's lots that you can do to help cut down on symptoms.
