hi Betsy..Thanks for your query.
Addison’s disease is a rare and chronic endocrine disorder in which the
adrenal glands do not produce sufficient steroid hormones.The most common symptoms are
fatigue, light headedness upon standing,
muscle weakness, fever,
weight loss etc.as of skin changes, hyper pigmentation is noted in sun-exposed areas, as well as darkening of the palmar creases, sites of friction, recent scars, the vermilion border of the lips, and genital skin.Are you noting any of these?The skin changes you have mentioned , do not point towards the above and i don't think that can be the only basis of the suspicion of addison's disease.
However, you have not described the 'odd' rash you are having .But since it is a chronic disorder persisting since 4 years , it is necessary you visit a
dermatologist and undergo a biopsy to know the exact nature of the eruptions.
Hope this helps..Take care!