Diagnosis inquiry

Hi,
My brother is 55 years old
He suffers from widespread pain and burning all over his body (always shown as episodes) and pain in the four limbs , redness in the eyes .
He did a lot of blood tests (but results where normal; for instance no vitamin d deficiency and rheumatoid factor was normal ..) , he also did x ray to check the glands but everything was normal .
He was diagnosed with fibromyalgia, so he started taking antidepressants and analgesics… but the case is getting worse and the pain is getting back….
So could you please advise
Thanks