@ipg, I was underweight when I started these medications, so maybe I needed to gain weight? One osteoporosis specialist thought that I may have improved my DEXA just by gaining weight. Yes, the weight gain happened over the two years. Your are right, these medications can cause constipation. I eat 6 prunes every night, which helps with bones and constipation. I am very sensitive to all medications. There are others who have written that they have no side effects. Unfortunately, the only way to find out how you will respond is to try it. The positive thing with Forteo is that it only lasts for about 4 hours. If you take one shot, you can always not take another one. This is so much safer than taking Prolia or Reclast that stay in your system 6 months and a year. Some people have written that the fatigue goes away fairly quickly with Forteo. I think Forteo made me relax too much. If you are anxious, it might feel good to relax. My issue with all of these anabolic medications is that they want you to take Prolia or Reclast to lock in gains. I have decided to try an estrogen patch instead. So far it is working, but it hasn't really been long enough to tell.