Hello, Thanks for the query, Prolia is monoclonal antibodies are made to target and destroy only certain cells in the body. It has certain side effects too . One of the most common side effect is rashes , which you also mentioned in your query . Usually doctor steroid drugs along with prolia specially to the people who are getting such symptoms . I would suggest you to consult your doctor about it . Doctor may alter the dose ,prescribe substitute or prescribe steroid medication ( Deltacortril ). Till then give cold compresses to affected area and take zyetec . Wishing you a good health. Thank you Dr Harry Maheshwari