People that experience intense pain as a result of injury usually take large quantities of pain medication and it’s more often than not Opiate based or take Valium. The sad fact is is that they do this because they are totally addicted to the medication and they enjoy the feeling the medication provides. He’s addicted and without professional guidance, pain management and most importantly your sons 100% cooperations to reduce his medication then nothing will change. If you haven’t discussed this with him do it sooner. Take care