hi. I have this problem too. I have always thought it happens when an infection starts to emerge. But I could be wrong. I have had constant muscle pain and fever on and off for about 5 years. I could be totally wrong but when this happens I also have allot of mucus that I cough up. It is very frustrating. If you find any other cause of this besides infection...let me know. Would love to hear that it might be something else. Btw I always culture either MRSA or PA.
don
don