Dexona Tablets (Dexamethasone) is used to treat symptoms such as inflammation, certain immune disorders and in replacement therapy of an inactive or underactive adrenal gland. Dexamethasone may be prescribed for skin allergies, asthma, leukaemia, blood disorders, selected rheumatic disorders, gastrointestinal disorders, skin problems, certain abnormal growths (cancers) and excessive calcium in the blood.