How Can Skin Seborrhea With Rashes, Swelling And Painful Itching Be Treated?

Doctor, My father is 80 yrs old and he's suffering from seborrhoea on skin for more than 6 months . His face , neck and chest areas are affected with sort of deep red rashes like. some areas are swollen that are painful and itching. He tried Allopathy but of no relief infact it became aggravated. He is now under Homeopathy treatment for past 4 or 5 months but no relief. in fact in the beginning there was some respite in the beginning under the treatment of homepathy but now no relief at all . could you suggest some remedy for this?