@candrgonzalez a friend of mine just has acid reflux and Fosamax really inflamed her esophagus. I have acid reflux and a generally horrible g.i. tract and opted for Prolia. Prolia has caused side effects (mentioned on this site before. Recap: made my IBS-C worse, made my arthritis worse, made my high cholesterol worse). Decision re taking 4th injection or taking Reclast instead, or not treating the osteoporosis and risking rebound fractures from going off Prolia without a backup drug. Have until July to decide. Prolia has not caused acid reflux issues for me. All drugs cause side effects. You dont know until you give it a go. Its the old risk vs benefit.

@candrgonzalez it is important to remember that some patients can take Prolia and other bisphosphonates without adverse side effects. People who don't experience side effects tend not to post on forums like this one. My mother has taken Prolia for years, an injection every 6 months. She experiences only the benefits and no side effects. I'm not saying you should or should not take Prolia, I just wanted to provide another story and person's experience.
Please talk to your doctor, tell her/him about your concerns and ask about possible alternatives and how risky the risk may or may not be for you. Like @sue225 says, everyone is different. You need to do what is right for you.

Side effects are different for each person. I tried Fosamax but it would not stay in my stomach longer than 10 minutes. Then my dr. recommended Prolia. After doing a lot of research and reading I found this site and made the decision to give Prolia a try. Had my first injection yesterday and so far so good. Good luck with whatever you decide to do.