What Causes Inflammation Of Wrists And Ankles Inpsite Of Being On HCG Injections?

i HAVE been taking HCG injections off and on for 5 years. I am now 62. When i first did It I lost 40 pounds and felt great. the last two times, however, I got inflammation of wrists and ankles and wondered if I was developing an allergy to HCG. My colleague at the office also experienced this and immediately stopped. I do not want to jeapardize my health...I am pretty athletic- but I have regained 15 pounds and have 3 vials of injectable HCG to use. Is there a possible connection between the joints and HCG? An allergy starting?