Suggest Remedy For Mild Pain In Legs And Forearm

Hello, my son has on set periods of pain, mild, to the legs, forearm since he was 3 years old. There is no other characteristic other than the pain that comes and goes and it changes place, there is no swelling or bruises. All his exams (ANA etc.) results are ok and because of this he does not want to give him a referral to see a specialist. What can I do? This situation is frustrating.