If you're reading this, you already know me
Another study looking at the results of many different studies indicates that those who take Prilosec and Zantac have an increased risk of pneumonia. The authors take their data from randomized trials of these drugs, which means that the study takes into account appropriately that people prescribed these drugs have acid reflux, which in itself increases pneumonia. Purely observational studies looking at people who are taking or not taking these drugs suffer from the fact that they cannot separate gastro-esophageal reflux disease (GERD) from the drugs used to treat it.
This study makes it more likely that proton pump inhibitors like Prilosec (omeprazole) and histamine blockers like Zantac (ranitidine) actually contribute to causing pneumonia in the people who take them.
If you take them, I suggest you ask your doctor to consider your doing without and seeing how you feel. Often people are on these for years after experiencing some episodes of gastrointestinal distress without any need for them.
http://www.ncbi.nlm.nih.gov/pubmed/21173070?dopt=Abstract