Hello and welcome to HCM, All the diseases that you have mentioned need to be managed separately. Osteoarthritis has to be managed with hyaluronic acid capsules or gel, physiotherapy and pain killers. Rheumatoid arthritis has to be managed by a group of drugs called disease modifying drugs and physiotherapy. Fibromyalgia has to be managed by various modalities to control muscle pain and deal with sleep problems. Irritable bowel syndrome has also to be managed symptomatically. A number of co-existent problems tends to cause depression and low feeling. The low mood has to be managed with appropriate medication and counseling. However, the diseases have to be managed individually. Thus, stay in touch with your psychiatrist and concerned doctors as well. Thanks and take care Dr Shailja Puri