Key takeaways
Alendronate (Fosamax) and Prolia (denosumab) are both used to treat osteoporosis, but they work differently and are taken in different ways. Alendronate (Fosamax) is a bisphosphonate that you take by mouth, either daily or weekly, and it helps by slowing down bone breakdown. Prolia (denosumab), on the other hand, is a monoclonal antibody given as an injection under the skin every six months by a healthcare professional. While alendronate (Fosamax) can cause stomach pain and heartburn, Prolia (denosumab) can lead to low calcium levels and back pain. Alendronate (Fosamax) requires you to stay upright for 30 minutes after taking it, whereas using Prolia (denosumab) requires that you take calcium and vitamin D supplements daily. Both medications can cause serious jaw problems, but Prolia (denosumab) has a higher risk of causing infections.
