I am on my third weekly treatment of chemotherapy, and have 9 more weeks to go. I have never had digestion or reflux problems before, but I am experiencing constipation, gas, reflux and burping. Is there anything over the counter I can take, especially for reflux? Reflux has prompted vomiting, and I want to avoid that. I would rather not take ranitidine or additional prespecriptions if I can help it.