I am a 83 yr old female. Always had a beautiful complexion and good skin. Three yrs ago I started rash on shoulders throat,chest and "rosacea" on face. Body very itchy...been told it is psoriasis, eczema, rosacea by dermatologists..prescribed various meds, ointments,etc. Is there some test that would correctly identify this ...allergy..? I take several meds.....Losartan Bystolic warfarin. I have an artificial mitral valve.