After having spinal fusion my and severe osteoporosis my surgeon recommended I get on Tymlos. I had the same problem with Tymlos including fast pulse, heart rate and headache issues. My Endocrinologist recommended Forteo. After 5 months on Forteo I was dealing with headaches and was considering getting off that also. I read in here about a study where patients took Forteo first thing in mornings and the findings were that it was more effective in bone growth than the others in the study group. As a last resort due to headache issues with Forteo I gave the morning injections a try. The headaches immediately went away. I was considering getting off Forteo until I tried the morning injections solution. I have now been on Forteo for 5 months and feel like I may be able to make the two year time frame. Best of luck.